ALISKIREN

ALISKIREN

(2S,4S,5S,7S)-5-amino-N-(2-carbamoyl-2,2-dimethylethyl)-4-hydroxy-7-{[4-methoxy-3-(3-methoxypropoxy)phenyl]methyl}-8-methyl-2-(propan-2-yl)nonanamide,  CAS 173334-57-1, base

CAS 173334-58-2,aliskiren hemifumarate

Aliskiren is a renin inhibitor. It was approved by the U.S. Food and Drug Administration in 2007 for the treatment of hypertension.

2-C30-H53-N3-O6.C4-H4-O4

1219.599

Novartis (Originator), Speedel (Licensee)

CARDIOVASCULAR DRUGS, Heart Failure Therapy, Hypertension, Treatment of, Renal Failure, Agents for, RENAL-UROLOGIC DRUGS, Treatment of Renal Diseases, Renin Inhibitors

Tekturna contains aliskiren hemifumarate, a renin inhibitor, that is provided as tablets for oral administration. Aliskiren hemifumarate is chemically described as (2S,4S,5S,7S)-N-(2-carbamoyl-2-methylpropyl)-5-amino-4-hydroxy-2,7diisopropyl-8-[4-methoxy-3-(3-methoxypropoxy)phenyl]-octanamide hemifumarate and its structural formula is

Molecular formula: C30H53N3O6 • 0.5 C4H4O4

Aliskiren hemifumarate is a white to slightly yellowish crystalline powder with a molecular weight of 609.8 (free base- 551.8). It is soluble in phosphate buffer, n-octanol, and highly soluble in water.

COUNTRY PATENT NUMBER APPROVED EXPIRES (ESTIMATED) Canada 2147056 2005-10-25 2015-04-13 United States 5559111 1998-07-21 2018-07-21

Aliskiren (INN) (trade names Tekturna, US; Rasilez, UK and elsewhere) is the first in a class of drugs called direct renin inhibitors. Its current licensed indication is essential (primary) hypertension.

Aliskiren was co-developed by the Swiss pharmaceutical companies Novartis andSpeedel.[1][2] It was approved by the US Food and Drug Administration in 2007 for the treatment of primary hypertension.[3]

In December 2011, Novartis had to halt a clinical trial of the drug after discovering increased incidence of nonfatal stroke, renal complications, hyperkalemia, and hypotension in patients with diabetes and renal impairment (ALTITUDE Trial ).[4] [5]

As a result, in April 20, 2012:

A new contraindication was added to the product label concerning the use of aliskiren with angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) in patients with diabetes because of the risk of renal impairment, hypotension, and hyperkalemia.

A warning to avoid use of aliskiren with ARBs or ACEIs was also added for patients with moderate to severe renal impairment (i.e., where glomerular filtration rate is less than 60 ml/min).

Renin, the first enzyme in the renin-angiotensin-aldosterone system, plays a role in blood pressure control. It cleaves angiotensinogen to angiotensin I, which is in turn converted byangiotensin-converting enzyme (ACE) to angiotensin II. Angiotensin II has both direct and indirect effects on blood pressure. It directly causes arterial smooth muscle to contract, leading to vasoconstriction and increased blood pressure. Angiotensin II also stimulates the production of aldosterone from the adrenal cortex, which causes the tubules of the kidneys to increase reabsorption of sodium, with water following, thereby increasing plasma volume, and thus blood pressure. Aliskiren binds to the S3bp binding site of renin, essential for its activity.[6] Binding to this pocket prevents the conversion of angiotensinogen to angiotensin I. Aliskiren is also available as combination therapy withhydrochlorothiazide.[7]

Many drugs control blood pressure by interfering with angiotensin or aldosterone. However, when these drugs are used chronically, the body increases renin production, which drives blood pressure up again. Therefore, doctors have been looking for a drug to inhibit renin directly. Aliskiren is the first drug to do so.[8][9]

Aliskiren may have renoprotective effects independent of its blood pressure−lowering effect in patients with hypertension, type 2 diabetes, and nephropathy, who are receiving the recommended renoprotective treatment. According to the AVOID study, researchers found that treatment with 300 mg of aliskiren daily, as compared with placebo, reduced the mean urinary albumin-to-creatinine ratio by 20%, with a reduction of 50% or more in 24.7% of the patients who received aliskiren as compared with 12.5% of those who received placebo. Furthermore, the AVOID trial showed treatment with 300 mg of aliskiren daily reduces albuminuria in patients with hypertension, type 2 diabetes, and proteinuria, who are receiving the recommended maximal renoprotective treatment with losartan and optimal antihypertensive therapy. Therefore, direct renin inhibition will have a critical role in strategic renoprotective pharmacotherapy, in conjunction with dual blockade of the renin−angiotensin−aldosterone system with the use of ACE inhibitors and angiotensin II–receptor blockers, very high doses of angiotensin II−receptor blockers, and aldosterone blockade.[10]

Aliskiren is a minor substrate of CYP3A4 and, more important, P-glycoprotein:

• It reduces furosemide blood concentration.
• Atorvastatin may increase blood concentration, but no dose adjustment is needed.
• Due to possible interaction with ciclosporin, the concomitant use of ciclosporin and aliskiren is contraindicated.
• Caution should be exercised when aliskiren is administered with ketoconazole or other moderate P-gp inhibitors (itraconazole, clarithromycin, telithromycin, erythromycin, or amiodarone).
• Doctors should stop prescribing aliskiren-containing medicines to patients with diabetes (type 1 or type 2) or with moderate to severe kidney impairment who are also taking an ACE inhibitor or ARB, and should consider alternative antihypertensive treatment as necessary.[13]
• Aliskiren (I) is a second generation renin inhibitor with renin-angiotensin system (RAS) as its target. It’s used clinically in the form of Aliskiren hemifumarate (Rasilez®) and was approved by FDA in May, 2007.

•  Aliskiren has the chemical name: (2S, 4S, 5S, 7S)-5-amino-N-(2-carbamoyl-2-methylpropyl)-4-hydroxy-2-isopropyl-7-[4-methoxy-3-(3-methoxypropoxy)benzyl]-8-methyloctanamide (CAS No.: 173334-57-1). Its chemical structure is illustrated with Formula I given below:
  
•  The method of preparation for Aliskiren and its intermediates has been reported in US7132569 , WO0208172 , US5559111 (equivalent patent toCN1266118 ), US5606078 , CN101016253 , WO2007/045421 ,EP2062874 , Helvetica ChimicaActa (2005, 3263-3273).
• In US7132569 , WO0208172 et al., the preparation of Aliskiren (I) comprises the following steps as described in reaction scheme 1: coupling 2-(3-methoxypropoxy)-4-((R)-2-(bromomethyl)-3-methylbutyl)-1-methoxybenzene (II) with (2S, 4E)-5-chloro-2-isopropyl-4-pentenoic acid derivative (III) to obtain the compound of formula IV; halolactonization of the compound of formula IV to obtain the compound of formula V; then substituting the compound of formula V with azide to obtain the compound of formula VI; ring-opening the compound of formula VI with 3-amino-2,2-dimethylpropionamide (VII) in the presence of 2-hydroxypyridine and triethylamine to obtain the compound of formula VIII and a final catalytic hydrogenation of the compound of formula VIII to obtain Aliskiren (I). This preparation process is illustrated in Reaction Scheme 1.
  
• In the patented preparation described above, chiral starting materials with the compounds of formula II and III are utilized to obtain the compound of formula IV. However, the reactions followed after the preparation of the compound of formula IV, such as the halolactonization and especially the substitutive reaction between the compound of formula V and azide, have problems of low yields and numerous by-products, which is not conducive to industrial scale production.
•  US5559111 (equivalent patent CN1266118 ) and US5606078 et al. report the preparation of the compound of formula XI via Grignard reaction with 4-bromo-1-methoxy-2-(3-methoxypropoxy)benzene (IX) and the compound of formula X as starting materials as illustated in Reaction Scheme 2:
  
• In the patented preparation described above, there are multiple reaction steps in the preparation of the compound of formula X from the compound of formula XII. The key steps, as described in Reaction Scheme 3, involve selective reduction agents such as sodium tri-tert-butoxyaluminum hydride and diisobutylaluminium hydride to prepare aldehyde and the reaction conditions need to be very well-controlled.
  
  
• [0009]
  The compound of formula XI prepared by reaction scheme 2 could then be converted into Aliskiren (I) after multiple catalytic hydrogenation, protection and de-protection. In this method of preparation, a stepwise catalytic hydrogenation, azido reduction and dehydroxylation were implemented to reduce by-products during the catalytic hydrogenation. In addition, it is necessary to protect and de-protect the free hydroxyl group during the preparation. This synthetic scheme has disadvantage of multiple synthetic steps, tedious operation, lengthy overall reaction duration, low yield and particularly high production cost for the starting compound of formula X.
• WO2007/045421 has reported an improved preparation method in which the starting material 4-bromo-1-methoxy-2-(3-methoxypropoxy)benzene (IX) firstly reacts with the compound of formula XIII via Grignard reaction to obtain the compound of formula XIV, and then followed by catalytic hydrogenation and ketone reduction to yield the compound of formula XV-A, as illustrated in Reaction Scheme 4:
  
  
•  In the above preparation, expensive reagents, such as sodium tri-tert-butoxyaluminum hydride and diisobutylaluminium hydride were eliminated, but additional synthetic steps were introduced. In addition, the preparation of the compound of formula XV-A prepared from the compound of formula XIV via ketone reduction required extended reaction time, great amount of catalyst with multiple small addition and good operation skills.
•  EP2062874A1 provides a method in preparing the compound of formula XVI. In this method, the compound of formula XVII is obtained from the compound of formula XVI via halogenation. A corresponding Grignard reagent is firstly prepared from the compound of formula IX or XVII reacting with magnesium, which is then couples with another chemical in the presence of the metal catalyst iron(III) acetylacetonate (Fe(acac)3) to obtain the compound of formula XVIII as described in Reaction Scheme 5:
  

  
• In EP2062874A1 , the compound of formula XVIII reacts with 3-amino-2,2-dimethylpropionamide (VII). The resulted product is then through reduction of the azio group to obtain Aliskiren (I). In this patent, detailed experimental protocol was not provided although N-methylpyrrolidone was mentioned as solvent. We found: 1) it is difficult to prepare the Grgnard reagent from the compound of formula IX; 2) the compounds of formula XVII and XVIII are not quite stable in the presence of iron(III) acetylacetonate. In addition, the yield in preparing the compound of formula XVIII was extremely low.

the spiro aldehyde (XLVII) is treated with N-benzylhydroxylamine in dichloromethane to give nitrone (LII), which is submitted to a Grignard reaction with the magnesium derivative of intermediate (XXX) in THF to afford the adduct (LIII) as a mixture of epimers at the amino group. Simultaneous N-dehydroxylation and cleavage of the spiro function of (LIII) by means of Zn, Cu (OAc) 2 in AcOH / water gives lactone (LIV), which is condensed with 3-amino- 2,2-dimethylpropionamide (XIX) by means of TEA and 2-hydroxypyridine giving the adduct (LV). Finally, the benzylamino group of (LV) is removed with H2 over Pd / C in methanol to yield a mixture of two epimers at the amino group, from which aliskiren is separated.

Tetrahedron Lett2001, 42, (29): 4819

NMR

ALISKIREN BASE

EP2546243A1

MS m/z: 552.6 (M+H)+; 1H-NMR (400 MHz, CDCl3) δ 6.88-6.75 (m, 3H), 4.08-4.04 (t, J = 6.3Hz, 2H), 3.79 (s, 3H), 3.60-3.55 (t, J = 6.3Hz, 2H), 3.30 (s, 3H), 3.30-3.25 (m, 3H), 2.69 (m, 2H), 2.49 (m, 1H), 2.27 (m, 1H), 2.04 (m, 2H), 1.78-1.35 (m, 7H), 1.10 (m, 6H), 0.90 (m, 12H) ppm.

Paper

A novel synthesis of the renin inhibitor aliskiren based on an unprecedented disconnection between C5 and C6 was developed, in which the C5 carbon acts as a nucleophile and the amino group is introduced by a Curtius rearrangement, which follows a simultaneous stereocontrolled generation of the C4 and C5 stereogenic centers by an asymmetric hydrogenation. Operational simplicity, step economy, and a good overall yield makes this synthesis amenable to manufacture on scale.

Convergent Synthesis of the Renin Inhibitor Aliskiren Based on C5–C6 Disconnection and CO2H–NH2 Equivalence

Elena Cini†, Luca Banfi§, Giuseppe Barreca‡, Luca Carcone‡, Luciana Malpezzi∥, Fabrizio Manetti†, Giovanni Marras‡, Marcello Rasparini*‡,Renata Riva§, Stephen Roseblade⊥, Adele Russo†, Maurizio Taddei*†, Romina Vitale§, and Antonio Zanotti-Gerosa⊥

† Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via A. Moro 2, 53100 Siena, Italy

‡Chemessentia SRL, Via Bovio 6, 28100 Novara, Italy

§ Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, Via Dodecaneso 31, 16146 Genova, Italy

∥ Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy

⊥Johnson Matthey Catalysis and Chiral Technologies, 28 Cambridge Science Park, Milton Road, Cambridge CB4 0FP, United Kingdom

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00396

Publication Date (Web): January 5, 2016

Copyright © 2016 American Chemical Society

*E-mail: mraspari@ITS.JNJ.com., *E-mail: maurizio.taddei@unisi.it.

http://pubs.acs.org/doi/abs/10.1021/acs.oprd.5b00396

http://pubs.acs.org/doi/suppl/10.1021/acs.oprd.5b00396/suppl_file/op5b00396_si_006.pdf

PAPER

 

http://pubs.rsc.org/en/content/articlelanding/2006/ob/b608028f

PAPER

http://pubs.rsc.org/en/content/articlelanding/2015/ob/c4ob01963f#!divAbstract

http://www.drugfuture.com/synth/syndata.aspx?ID=267580

EP 0678500; EP 0678503; JP 1996053434; JP 1996081430; US 5559111; US 5627182; US 5646143

Alkylation of 3-hydroxy-4-methoxybenzyl alcohol (I) with 1-bromo-3-methoxypropane (II) gives ether (III). Subsequent conversion of benzyl alcohol (III) into bromide (IV) is carried out using bromotrimetylsilane. The chiral isovaleryloxazolidinone (V) is alkylated with bromide (IV) by means of LiHMDS to afford (VI), which is hydrolyzed to the (S)-2-aryl-2-isopropylpropionic acid (VII) by means of lithium peroxide. The reduction of acid (VII) to the corresponding alcohol with NaBH4/I2 reagent, followed by treatment with PPh3 and NBS, provides bromide (VIII). Alkylation of the chiral dimethoxydihydropyrazin (IX) with bromide (VIII) produces (X). Further hydrolysis of the pyrazine ring of (X) with HCl, followed by Boc protection of the resulting (S,S)-amino ester, yields compound (XI). Reduction of the ester group of (XI) with DIBAL gives aldehyde (XII). This compound is condensed with the Grignard reagent (XIII) to afford the diastereomeric mixture of amino alcohols (XIV). Treatment of mixture (XIV) with 2,2-dimethoxypropane (XV) and TsOH produces a mixture of oxazolidines, from which the required (S,S,S)-isomer (XVI) is isolated by flash chromatography. Hydrogenolitic deprotection of the benzyl ether of (XVI) gives alcohol (XVII).

This alcohol is oxidized to aldehyde with NMMO and tetrapropylammonium perruthenate (TPAP), and further oxidized to carboxylic acid (XVIII) with KMnO4 and tetrabutylammonium bromide (TBAB). Coupling of (XVIII) with aminoamide (XIX) by means of diethyl cyanophosphonate and TEA gives (XX). Finally, acid hydrolysis of the oxazolidine ring and Boc protecting groups of (XX) furnishes the corresponding amino alcohol, which is finally converted to the hemifumarate salt.

WO 0109079; WO 0109083

 Alternatively, the chiral azido intermediate (XXXIV) can also be synthesized as follows: Alkylation of oxazolidinone (V) with 1-chloro-3-iodopropene (XLVIII) by means of LiHMDS in THF gives compound (XLIX), which is condensed with the magnesium derivative of the phenylpropyl chloride (XXX) to yield, after working up, amide (L). Bromination of (L) with NBS and phosphoric acid affords the bromolactone (LI), which by treatment with NaN3 in tripropylene glycol/water provides the azido derivative (XXXIV).

WO 0202500

The condensation of benzaldehyde (I) with ethyl isovalerate (II) by means of hexyl lithium and DIA in THF gives the hydroxyester (III), which is acylated with Ac2O and DMAP in THF to yield the acetoxy derivate (IV). The elimination reaction in (IV) by means of t-BuOK in THF affords the unsaturated ester (V), which is hydrolyzed with KOH in ethanol to provide the unsaturated free acid (VI). Finally, this compound is enantioselectively reduced with H2 over several chiral Rh catalysts {[Rh(NBD)2BF4, [Rh(NBD)(OCOCF3)2], [Rh(NBD)Cl2], etc} to give the target intermediate 2(R)-isopropyl-3-[4-methoxy-3-(3-methoxypropoxy)phenyl]propionic acid (VII). (see scheme 26758001a, intermediate (VII)).

WO 0208172

The condensation of ethyl isovalerate (I) with 1,3-dichloropropene (II) by means of BuLi and DIA in THF gives 5-chloro-2-isopropyl-4-pentenoic acid ethyl ester (III), which is hydrolyzed with NaOH in ethanol to yield the corresponding racemic acid (IV). The optical resolution of (IV) is carried out by means of cinchonidine and TEA in THF to afford 5-chloro-2(S)-isopropyl-4-pentenoic acid (V), which can also be obtained by asymmetric synthesis as follows: Condensation of 4(S)-benzyl-3-(3-methylbutyryl)oxazolidin-2-one (VI) with 3-iodo-1-propenyl chloride (VII) by means of LiHMDS in THF gives 4(S)-benzyl-3-(2(S)-isopropyl-3-methylbutyryl)oxazolidin-2-one (VIII), which is hydrolyzed with LiOH in THF/water to afford the chiral pentanoic acid (V). The reaction of (V) with oxalyl chloride in toluene gives the corresponding acyl chloride (IX), which is treated with dimethylamine and pyridine in dichloromethane to yield the dimethylamide (X). The condensation of (X) with the chiral chloro derivative (XI) (obtained by reaction of the corresponding alcohol (XII) with CCl4 and trioctylphosphine) by means of Mg and 1,2-dibromoethane in THF affords the octenamide (XIII). The cyclization of (XIII) by means of phosphoric acid and simultaneous bromination with NBS in THF provides the chiral bromolactone (XIV), which is opened by means of dimethylamine and Et2AlCl in dichloromethane to give the chiral 5-bromo-4-hydroxy-2,7-diisopropyloctanamide (XV). The reaction of (XV) with acetic anhydride and pyridine in dichloromethane yields the acetoxy derivative (XVI), which is treated with LiN3 to afford the 5(S)-azido derivative (XVII).

The cyclization of (XVII) by means of TsOH in refluxing methanol gives the chiral lactone (XVIII), which is condensed with 3-amino-2,2-dimethylpropionamide (XIX) by means of TEA and 2-hydroxypyridine at 90 C to yield the corresponding amide (XX). Finally, the azido group of (XX) is reduced with H2 over Pd/C in tert-butyl methyl ether to afford the target Aliskiren.

WO 0202508

The condensation of the chiral chloro derivative (I) with 5-chloro-[2(S)-isopropyl]-4-pentanoic acid methyl ester (II) by means of Mg and dibromoethane in THF gives the chiral octenoic ester (III) which is converted to the corresponding acid (IV) by means of LiOH in THF/methanol/water. The reaction of (IV) with NBS in dichloromethane yields the bromolactone (V), which is treated with LiOH in isopropanol to yield the epoxide (VI). This compound, without isolation, is treated with HCl in the same solvent to afford the chiral hydroxylactone (VII). The reaction of the OH group of (VII) with MsCl and pyridine in toluene provides the mesylate (VIII), which is treated with NaN3 in hot 1,3-dimethylperhydropyrimidin-2-one to give the azido derivative (IX). The condensation of (IX) with 3-amino-2,2-dimethylpropionamide (X) by means of 2-hydroxypyridine in hot TEA yields the carboxamide (XI). Finally, the azido group of (XI) is reduced with H2 over Pd/C in tert-butyl methyl ether to provide the target Aliskiren.

Tetrahedron Lett 2000,41(51),10085

The intermediate gamma-butyrolactone (XXVIII) has been obtained as follows: Allylation of the imidazolidinone intermediate (V) with allyl bromide (XXI) and LiHMDS in THF gives the chiral intermediate (XXII), which by dihydroxylation and cleavage of the chiral auxiliary with OsO4 and NMMO in tert-butanol/acetone/water yields the lactone alcohol (XXIII). Oxidation of (XXIII) with NaIO4 and RuCl3 in CCl4/acetonitrile/water affords the carboxylic acid (XXIV), which by treatment with (COCl)2 in toluene provides the acyl chloride (XXV). Esterification of (XXV) with benzyl alcohol gives the corresponding benzyl ester as a diastereomeric mixture, from which the desired isomer (XXVI) is separated by flash chromatography. Hydrogenolysis of the benzyl ester (XXVI) with H2 over Pd/C in ethyl acetate yields the carboxylic acid (XXVII), which is treated with oxalyl chloride in toluene to afford the desired gamma-butyrolactone intermediate (XXVIII).

SEE…….http://www.drugfuture.com/synth/syndata.aspx?ID=267580

1. Gradman A, Schmieder R, Lins R, Nussberger J, Chiang Y, Bedigian M (2005). “Aliskiren, a novel orally effective renin inhibitor, provides dose-dependent antihypertensive efficacy and placebo-like tolerability in hypertensive patients”. Circulation 111 (8): 1012–8.doi:10.1161/01.CIR.0000156466.02908.ED. PMID 15723979.
2.  Straessen JA, Li Y, and Richart T (2006). “Oral Renin Inhibitors”. Lancet 368 (9545): 1449–56. doi:10.1016/S0140-6736(06)69442-7. PMID 17055947.
3. “First Hypertension Drug to Inhibit Kidney Enzyme Approved”. CBC. 2007-03-06. Retrieved 2007-03-14.[dead link]
4. Healthzone.ca: Blood-pressure drug reviewed amid dangerous side effects
5.  Parving, Hans-Henrik; Barry M. Brenner, M.D., Ph.D., John J.V. McMurray, M.D., Dick de Zeeuw, M.D., Ph.D., Steven M. Haffner, M.D., Scott D. Solomon, M.D., Nish Chaturvedi, M.D., Frederik Persson, M.D., Akshay S. Desai, M.D., M.P.H., Maria Nicolai
6. Alkylation of 3-hydroxy-4-methoxybenzyl alcohol (I) with 1-bromo-3-methoxypropane (II) gives ether (III). Subsequent conversion of benzyl alcohol (III) into bromide (IV) is carried out using bromotrimetylsilane. The chiral isovaleryloxazolidinone (V) is alkylated with bromide (IV) by means of LiHMDS to afford (VI), which is hydrolyzed to the (S)-2-aryl-2-isopropylpropionic acid (VII) by means of lithium peroxide. The reduction of acid (VII) to the corresponding alcohol with NaBH4/I2 reagent, followed by treatment with PPh3 and NBS, provides bromide (VIII). Alkylation of the chiral dimethoxydihydropyrazin (IX) with bromide (VIII) produces (X). Further hydrolysis of the pyrazine ring of (X) with HCl, followed by Boc protection of the resulting (S,S)-amino ester, yields compound (XI). Reduction of the ester group of (XI) with DIBAL gives aldehyde (XII). This compound is condensed with the Grignard reagent (XIII) to afford the diastereomeric mixture of amino alcohols (XIV). Treatment of mixture (XIV) with 2,2-dimethoxypropane (XV) and TsOH produces a mixture of oxazolidines, from which the required (S,S,S)-isomer (XVI) is isolated by flash chromatography. Hydrogenolitic deprotection of the benzyl ether of (XVI) gives alcohol (XVII).des, M.D., Alexia Richard, M.Sc., Zhihua Xiang, Ph.D., Patrick Brunel, M.D., and Marc A. Pfeffer, M.D., Ph.D. for the ALTITUDE Investigators (2012). “Cardiorenal End Points in a Trial of Aliskiren for Type 2 Diabetes”. NEJM 367 (23): 2204–13. doi:10.1056/NEJMoa1208799. PMID 23121378.
7. J “Chemistry & Biology : Structure-based drug design: the discovery of novel nonpeptide orally active inhibitors of human renin”. ScienceDirect. Retrieved 2010-01-20.
8.  Baldwin CM, Plosker GL.[1]. doi:10.2165/00003495-200969070-00004. Drugs 2009; 69(7):833-841.
9.  Ingelfinger JR (June 2008). “Aliskiren and dual therapy in type 2 diabetes mellitus”. N. Engl. J. Med. 358 (23): 2503–5.doi:10.1056/NEJMe0803375. PMID 18525047.
10.  PharmaXChange: Direct Renin Inhibitors as Antihypertensive Drugs
11.  Parving HH, Persson F, Lewis JB, Lewis EJ, Hollenberg NK. “Aliskiren Combined with Losartan in Type 2 Diabetes and Nephropathy,” N Engl J Med 2008;358:2433-46.
12.  Drugs.com: Tekturna
13.  Cardiorenal end points in a trial of aliskiren for type 2 diabetes, N Engl J MED. 2012;367(23):2204-2213
14. European Medicines Agency recommends new contraindications and warnings for aliskiren-containing medicines.

• Prescribing Information for Tekturna
• aliskiren at the US National Library of Medicine Medical Subject Headings (MeSH)
• Chemical synthesis

Drugs Fut2001, 26, (12): 1139

Tetrahedron Lett 2001, 42: 4819-23.

Tetrahedron Lett2000, 41, (51): 10085

EP 0678500; EP 0678503; JP 1996053434; JP 1996081430; US 5559111; US ​​5627182; US 5646143, WO 0109079; WO 0109083

ALISKIREN

SYSTEMATIC (IUPAC) NAME
(2S,4S,5S,7S)-5-amino-N-(2-carbamoyl-2,2-dimethylethyl)-4-hydroxy-7-{[4-methoxy-3-(3-methoxypropoxy)phenyl]methyl}-8-methyl-2-(propan-2-yl)nonanamide
CLINICAL DATA
AHFS/DRUGS.COM	monograph
MEDLINEPLUS	a607039
LICENCE DATA	EMA:Link, US FDA:link
PREGNANCY CATEGORY	C in first trimester D in second and third trimesters
LEGAL STATUS	UK: POM (Prescription only) US: ℞-only
ROUTES OF ADMINISTRATION	PO (oral)
PHARMACOKINETIC DATA
BIOAVAILABILITY	Low (approximately 2.5%)
METABOLISM	Hepatic, CYP3A4-mediated
BIOLOGICAL HALF-LIFE	24 hours
EXCRETION	Renal
IDENTIFIERS
CAS NUMBER	173334-57-1
ATC CODE	C09XA02 C09XA52 (with HCT)
PUBCHEM	CID: 5493444
IUPHAR/BPS	4812
DRUGBANK	DB01258
CHEMSPIDER	4591452
UNII	502FWN4Q32
KEGG	D03208
CHEBI	CHEBI:601027
CHEMBL	CHEMBL1639
CHEMICAL DATA
FORMULA	C30H53N3O6
MOLECULAR MASS	551.758 g/mol

SEE……..http://www.allfordrugs.com/2013/12/17/aliskiren/

////

O=C(N)C(C)(C)CNC(=O)[C@H](C(C)C)C[C@H](O)[C@@H](N)C[C@@H](C(C)C)Cc1cc(OCCCOC)c(OC)cc1

AT 9283

AT9283, AT 9283

N-cyclopropyl-N’-[3-[6-(4-morpholinylmethyl)-1H-benzimidazol-2-yl]-1H-pyrazol-4-yl]urea

1-cyclopropyl-3-[(3Z)-3-[5-(morpholin-4-ylmethyl)benzimidazol-2-ylidene]-1,2-dihydropyrazol-4-yl]urea

896466-04-9
Molecular Weight	381.43
Molecular Formula	C19H23N7O2

CAS

896466-04-9, 896466-57-2 ((±)-Lactic acid), 896466-61-8 (HCl), 896466-55-0 (methanesulfonate)

MolFormulaC22H29N7O5

MolWeight471.5096

CAS 896466-76-5  L LACTATE

(2S)-2-Hydroxypropanoic acid compd. with N-cyclopropyl-N’-[3-[6-(4-morpholinylmethyl)-1H-benzimidazol-2-yl]-1H-pyrazol-4-yl]urea

Astex Therapeutics Ltd, INNOVATOR

AT-9283 is a potent AuroraA/AuroraB and multi-kinase inhibitor. AT-9283 has shown to inhibit growth and survival of multiple solid tumor cell lines and is efficacious in mouse xenograft models.

AT 9283 is a substance being studied in the treatment of some types of cancer. It is small molecule a multi-targeted c-ABL, JAK2, Aurora A and B inhibition with 4, 1.2, 1.1 ad approximate 3 nM for Bcr-Abl (T3151), Jak2 and Jak3 aurora A and B, respectively. It blocks enzymes (Aurora kinases) involved in cell division and may kill cancer cells

WO2006070195 to Astex Therapeuitcs discloses pyrazole compounds of the general structure shown below as kinase inhibitors.

The compound AT9283 is in phase II clinical trials for treating advanced or metastatic solid tumors or Non-Hodgkin’s Lymphoma. AT9283 is shown below.

a Reagents and conditions:

(a) SOCl2, THF, DMF; (b) morpholine, THF, Et3N;  ………FORMATION OOF ACID CHLORIDE AND COUPLING WITH MORPHOLINE

(c) NaBH4, BF3.OEt2, THF; …………..KETO TO CH2

(d) 10% Pd-C, H2, EtOH; TWO NITRO GPS TO TWO AMINO , REDN

(e) EDC, HOBt, DMF; (f) AcOH, reflux;COUPLING WITH 4-Nitro-lH-pyrazole-3-carboxylic acid

(g) 10%Pd-C, H2, DMF; NITRO GP TO  AMINO

(h) standard amide and urea coupling methods

WO2006070195

https://www.google.co.in/patents/WO2006070195A1?cl=en

Stage 10: Synthesis of l-cvclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH- beiizoimidazol-2-ylV 1 H-pyrazol-4-yli -urea.

To a mixture of 7-morpholin-4-ylmethyl-2,4-dihydro- 1 ,2,4,5a, 10- pentaaza- cyclopenta[a]fluoren-5-one (10.7 g, 32.9 mmol) in NMP (65 mL) was added cyclopropylamine (6.9 mL, 99 mmol). The mixture was heated at 100 0C for 5 h. LC/MS analysis indicated -75% conversion to product, therefore a further portion of cyclopropylamine (2.3 mL, 33 mmol) was added, the mixture heated at 100 0C for 4 h and then cooled to ambient. The mixture was diluted with water (100 mL) and extracted with EtOAc (100 niL). The organic portion was washed with sat. aq. NH4Cl (2 x 50 mL) and brine (50 rnL) and then the aqueous portions re-extracted with EtOAc (3 x 100 mL). The combined organic portions were dried over MgSO4 and reduced in vacuo to give l-cycloρropyl-3-[3-(5-morpholin-4-ylmethyl-lH- benzoimidazol-2-yl)-lH-pyrazol-4-yl]-urea as an orange glassy solid (9.10 g).

Stage 11: Synthesis of l-cvclopropyl-S-P-fS-morpholin^-ylmethyl-lH- benzoimidazol-2-yl)-lH-pyrazol-4-yll-urea, L-lactate salt

To a solution of l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol-2- yl)-lH-pyrazol-4-yl]-urea (9.10 g, 24 mmol) in EtOAc-iPrOH (1 :1, 90 mL) was added L-lactic acid (2.25 g, 25 mmol). The mixture was stirred at ambient temperature for 24 h then reduced in vacuo. The residue was given consecutive slurries using toluene (100 mL) and Et2O (100 mL) and the resultant solid collected and dried (8.04 g).

This solid was purified by recrystallisation from boiling iPrOH (200 mL) to give after drying l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol-2-yl)- lH-pyrazol-4-yl]-urea, L-lactate salt (5.7 g) as a beige solid.

EXAMPLE 66

Stage 1: Preparation of (3,4-dinitrophenyl)-morpholin-4-yl-methanone

3,4-Dinitrobenzoic acid (1.000Kg, 4.71mol, l.Owt), tetiuhydrofuran (10.00L5 lO.Ovol), and dimethylformamide (0.010L, O.Olvol) were charged to a flask under nitrogen. Thionyl chloride (0.450L, 6.16mol, 0.45vol) was added at 20 to 3O0C and the reaction mixture was heated to 65 to 7O0C. Reaction completion was determined by 1H NMR analysis (d6-DMSO), typically in 3 hours. The reaction mixture was cooled to 0 to 50C and triethylamine (1.25L, 8.97mol, 1.25vol) was added at 0 to 100C. Morpholine (0.62L, 7.07mol, 0.62vol) was charged to the reaction mixture at 0 to 1O0C and the slurry was stirred for 30 minutes at 0 to 1O0C. Reaction completion was determined by H NMR analysis (d6-DMSO). The reaction mixture was warmed to 15 to 2O0C and water (4.00L, 4.0vol) was added. This mixture was then charged to a 4OL flange flask containing water (21.0OL, 21.0vol) at 15 to 250C to precipitate the product. The flask contents were cooled to and aged at 0 to 50C for 1 hour and the solids were collected by filtration. The filter-cake was washed with water (4x 5.00L, 4x 5.0vol) and the pH of the final wash was found to be pH 7. The wet filter-cake was analysed by H NMR for the presence of triethylamine hydrochloride. The filter-cake was dried at 40 to 450C under vacuum until the water content by KF <0.2%w/w, to yield (3,4-dinitrophenyl)-morpholin-4-yl-methanone (1.286Kg, 97.0%, KF 0.069%w/w) as a yellow solid.

Stage 2: Preparation of 4-(3,4-dinitro-benzyl)-morpholine

C11H11N3O6 C11H13N3O5

FW:281.22 FW:267.24

(3,4-DinitiOphenyl)-morpholin-4-yl-methanone (0.750Kg, 2.67mol, l.Owt) and tetrahydrofuran (7.50L, lO.Ovol) were charged to a flask under nitrogen and cooled to 0 to 50C. Borontrifluoride etherate (0.713L, 5.63mol, 0.95vol) was added at 0 to 50C and the suspension was stirred at this temperature for 15 to 30 minutes. Sodium borohydride (0.212Kg, 5.60mol, 0.282wt) was added in 6 equal portions over 90 to 120 minutes. (A delayed exotherm was noted 10 to 15 minutes after addition of the first portion. Once this had started and the reaction mixture had been re-cooled, further portions were added at 10 to 15 minute intervals, allowing the reaction to cool between additions). The reaction mixture was stirred at 0 to 50C for 30 minutes. Reaction completion was determined by 1H NMR analysis (d6-DMSO). Methanol (6.30L, 8.4vol) was added drop wise at 0 to 1O0C to quench the reaction mixture (rapid gas evolution, some foaming). The quenched reaction mixture was stirred at 0 to 1O0C for 25 to 35 minutes then warmed to and stirred at 20 to 3O0C (exotherm, gas/ether evolution on dissolution of solid) until gas evolution had slowed. The mixture was heated to and stirred at 65 to 7O0C for 1 hour. The mixture was cooled to 30 to 4O0C and concentrated under vacuum at 40 to 450C to give crude 4-(3,4-dinitro-benzyl)-morpholine (0.702Kg, 98.4%) as a yellow/orange solid.

4-(3,4-Dinitro-benzyl)-niorpholme (2.815kg, 10.53mol, l.Owt) and methanol (12.00L, 4.3vol) were charged to a flask under nitrogen and heated to 65 to 7O0C. The temperature was maintained until complete dissolution. The mixture was then cooled to and aged at 0 to 50C for 1 hour. The solids were isolated by filtration. The filter-cake was washed with methanol (2x 1.50L, 2x 0.5vol) and dried under vacuum at 35 to 45°C to give 4-(3,4-dinitro-benzyl)-morpholine (2.353Kg, 83.5% based on input Stage 2, 82.5% overall yield based on total input Stage 1 material,) as a yellow solid.

Stage 3: Preparation of 4-morpholin-4-yl-methyl-benzene-L2-diamine

C11H13N3O5 C11H17N3O

FW:267.24 FW:207.27

4-(3,4-Dinitro-benzyl)-morρholine (0.800Kg, 2.99mol, l.Owt), and ethanol (11.20L, 14.0vol) were charged to a suitable flask and stirred at 15 to 250C and a vacuum / nitrogen purge cycle was performed three times. 10% Palladium on carbon (10%Pd/C, 50%wet paste, 0.040Kg, 0.05wt wet weight) was slurried in ethanol (0.80L, l.Ovol) and added to the reaction. The mixture was cooled to 10 to 2O0C and a vacuum / nitrogen purge cycle was performed three times. A vacuum / hydrogen purge cycle was performed three times and the reaction was stirred under a hydrogen atmosphere at 10 to 2O0C. Reaction completion was determined by 1H NMR analysis (d6-DMSO), typically 14 to 20 hours. A vacuum / nitrogen purge cycle was performed three times and the reaction mixture was filtered through glass microfibre paper under nitrogen. The filter-cake was washed with ethanol (3x 0.80L, 3x l.Ovol) and the combined filtrate and washes were concentrated to dryness under vacuum at 35 to 450C to give 4-morpholin-4-yl-methyl-benzene-l,2- diamine (0.61 IKg 98.6%) as a brown solid.

Stage 4: Preparation of 4-nitiO-lH-pyrazole-3-carboxγlic acid methyl ester

C4H3N3O4 C5H5N3O4

FW: 157.09 FW: 171.11

4-Nitro-lH-pyrazole-3-carboxylic acid (1.00kg, 6.37mol, l.Owt) and methanol (8.00L, 8.0vol) were charged to a flange flask equipped with a mechanical stirrer, condenser and thermometer. The suspension was cooled to 0 to 5°C under nitrogen and thionyl chloride (0.52L, 7.12mol, 0.52vol) was added at this temperature. The mixture was warmed to 15 to 25°C over 16 to 24 hours. Reaction completion was determined by 1H NMR analysis (d6-DMSO). The mixture was concentrated under vacuum at 35 to 45°C. Toluene (2.00L, 2.0vol) was charged to the residue and removed under vacuum at 35 to 450C. The azeotrope was repeated twice using toluene (2.00L, 2.0vol) to give 4-nitro-lH-pyrazole-3-carboxylic acid methyl ester (1.071Kg, 98.3%) as an off white solid.

Stage 5: Preparation of 4-amino-lH-pyrazole-3-carboxylic acid methyl ester. O2Me

C5H 5N3O4 C5H7N3O2 FW: 171.11 FW: 141.13

A suspension of 4-nitro-lH-pyrazole-3-carboxylic acid methyl ester (1.084Kg, 6.33mol, l.Owt) and ethanol (10.84L, lO.Ovol) was heated to and maintained at 30 to 35°C until complete dissolution occurred. 10% Palladium on carbon (10% Pd/C wet paste, 0.152Kg, 0.14wt) was charged to a separate flask under nitrogen and a vacuum / nitrogen purge cycle was performed three times. The solution of 4-nitro- lH-pyrazole-3-carboxylic acid methyl ester in ethanol was charged to the catalyst and a vacuum / nitrogen purge cycle was performed three times. A vacuum / hydrogen purge cycle was performed three times and the reaction was placed under an atmosphere of hydrogen. The reaction mixture was stirred at 28 to 30°C until deemed complete by 1H NMR analysis (d6-DMSO). The mixture was filtered under nitrogen and concentrated under vacuum at 35 to 450C to give 4-amino-lH- pyrazole-3-carboxylic acid methyl ester (0.883Kg, 98.9%) as a purple solid.

Stage 6: Preparation of 4-fert-butoxycarbonylamino-lH-pyrazole-3-carboxylic acid

C5H7N3O2 C9H13N3O4

FW: 141.13 FW:227.22

4-Amino-lH-pyrazole-3-carboxylic acid methyl ester (1.024Kg, 7.16mol, l.Owt) and dioxane (10.24L, lO.Ovol) were charged to a flange flask equipped with a mechanical stirrer, condenser and thermometer. 2M aq. Sodium hydroxide solution (4.36L, 8.72mol, 4.26vol) was charged at 15 to 250C and the mixture was heated to 45 to 550C. The temperature was maintained at 45 to 550C until reaction completion, as determined by 1H NMR analysis (d6-DMSO). Di-te/Y-butyl dicarbonate (Boc anhydride, 1.667Kg, 7.64mol, 1.628wt) was added at 45 to 55°C and the mixture was stirred for 55 to 65 minutes. 1H NMR IPC analysis (d6-DMSO) indicated the presence of 9% unreacted intermediate. Additional di-fert-butyl dicarbonate (Boc anhydride, 0.141Kg, 0.64mol, 0.14wt) was added at 55°C and the mixture was stirred for 55 to 65 minutes. Reaction completion was determined by 1H NMR analysis (d6-DMSO). The dioxane was removed under vacuum at 35 to 450C and water (17.60L, 20.0vol) was added to the residue. The pH was adjusted to pH 2 with 2M aq. hydrochloric acid (4.30L, 4.20vol) and the mixture was filtered. The filter-cake was slurried with water (10.00L3 9.7vol) for 20 to 30 minutes and the mixture was filtered. The filter-cake was washed with heptanes (4.10L, 4.0vol) and pulled dry on the pad for 16 to 20 hours. The solid was azeodried with toluene (5x 4.00L, 5x 4.6vol) then dried under vacuum at 35 to 45°C to give 4-tert- butoxycarbonylamino-lH-pyrazole-3-carboxylic acid (1.389Kg, 85.4%) as a purple solid.

Stage 7: Preparation of [3-(2-amino-4-moipholin-4-ylmetliyl-phenylcarbamoviy lH-pyrazol-4-yl]-carbamic acid tert-butyl ester

C9H13N3O4 C11H17N3O C20H28N6O4

FW: 227.22 FW: 207.27 FW: 416.48

+ regioisomer

4-førf-Butoxycarbonylamino-lH-pyrazole-3-carboxylic acid (0.750Kg, 3.30 mol, l.Owt), 4-morpholin-4yl-methyl-benzene-l,2-diamine (0.752Kg, 3.63mol, l.Owt) and N,N’-dimethylformamide (11.25L, 15.0vol) were charged under nitrogen to a flange flask equipped with a mechanical stirrer and thermometer. 1- Hydroxybenzotriazole (HOBT, 0.540Kg, 3.96mol, 0.72wt) was added at 15 to 250C. N-(3-Dimethylaminopropyl)-N’-ethylcarbodiimide (EDC, 0.759Kg, 3.96mol, 1.01 wt) was added at 15 to 250C and the mixture was stirred at this temperature for 16 to 24 hours. Reaction completion was determined by 1H NMR analysis. The reaction mixture was concentrated under vacuum at 35 to 45°C. The residue was partitioned between ethyl acetate (7.50L, lO.Ovol) and sat. aq. sodium hydrogen carbonate solution (8.03L, 10.7vol) and the layers were separated. The organic phase was washed with brine (3.75L, 5.0vol), dried over magnesium sulfate (1.00Kg, 1.33wt) and filtered. The filter-cake was washed with ethyl acetate (1.50L, 2.0vol). The combined filtrate and wash were concentrated under vacuum at 35 to 450C to give [3-(2-amino-4-morpholin-4-ylmethyl-phenylcarbamoyl)-lH-pyrazol- 4-yl]-carbamic acid tert-butyl ester (1.217Kg, 88.6%) as a dark brown solid.

Stage 8 : Preparation of 3 -f 5-morpholin-4-ylmethyl- 1 H-benzoimidazol-2-ylV 1 H- pyrazol-4-ylamme

C15H19N6O

FW: 298.35

As a mixture of two regioisomers

[3-(2-Amino-4-morpholin-4-ylmethyl-phenylcarbamoyl)-lH-pyrazol-4-yl]- carbamic acid tert-butyl ester (1.350Kg, 3.24 mol, l.Owt) and ethanol (6.75L, 5.0vol) were charged to a flange flask equipped with a mechanical stirrer, condenser and thermometer. Cone. aq. hydrochloric acid (1.10L, 13.2 mol, 0.80vol) was added at 15 to 3O0C under nitrogen and the contents were then heated to 70 to 8O0C and maintained at this temperature for 16 to 24 hours. A second portion of hydrochloric acid (0.1 IL, 1.32 mol, O.OSOvol) was added at 70 to 8O0C and the reaction was heated for a further 4 hours. Reaction completion was determined by HPLC analysis. The reaction mixture was cooled to 10 to 200C and potassium carbonate (1.355Kg, 9.08mol, l.Owt) was charged portionwise at this temperature. The suspension was stirred until gas evolution ceased and was then filtered. The filter-cake was washed with ethanol (1.35L, l.Ovol) and the filtrates retained. The filter-cake was slurried with ethanol (4.00L, 3.0vol) at 15 to 250C for 20 to 40 minutes and the mixture was filtered. The filter-cake was washed with ethanol (1.35L3 1.Ovol) and the total combined filtrates were concentrated under vacuum at 35 to 450C. Ethanol (4.00L, 3. Ovol) was charged to the residue and removed under vacuum at 35 to 450C. Tetrahydrofuran (5.90L, 4.4vol) was added to the residue and stirred for 10 to 20 minutes at 15 to 25°C. The resulting solution was filtered, the filter-cake was washed with tetrahydrofuran (1.35L, l.Ovol) and the combined filtrates were concentrated under vacuum at 35 to 450C. Tetrahydrofuran (5.40L, 4. Ovol) was charged to the concentrate and removed under vacuum at 35 to 450C. Tetrahydrofuran (5.40L, 4. Ovol) was charged to the concentrate and removed under vacuum at 35 to 45°C to give the desired product, 3-(5-morpholin-4-ylmethyl-lH- benzoimidazol-2-yl)-lH-pyrazol-4-ylamine (0.924Kg, 95.5%, 82.84% by HPLC area) as a purple foam.

Stage 9: Preparation of 7-morpholin-4-ylmethyl-2,4-dihydro- 1,2,4,5a ,10-pentaaza- cyclopentaFal fluoren-5 -one

C15H18N6O C16H16N6O2 FW: 298.35 FW: 324.34

As a mixture of two regioisomers

3-(5-Morpholin-4-ylmethyl-lH-benzoimidazol-2-yl)-lH-pyrazol-4-ylamine (0.993Kg, 3.33 mol, l.Owt) and tetrahydrofuran (14.0L, 15.0vol) were charged to a flange flask equipped with a mechanical stirrer, condenser and thermometer. The contents were stirred under nitrogen at 15 to 25°C and l,l ‘-carbonyldiimidazole (0.596Kg, 3.67 mol, O.όOwt) was added. The contents were then heated to 60 to 700C and stirred at this temperature for 16 to 24 hours. Reaction completion was determined by TLC analysis. The mixture was cooled to 15 to 200C and filtered. The filter-cake was washed with tetrahydrofuran (4.00L, 4. Ovol) and pulled dry for 15 to 30 minutes. The solid was dried under vacuum at 35 to 450C to yield 7- morpholin-4-ylmethyl-2,4-dihydro- 1 ,2,4,5a, 10-pentaaza-cyclopenta[a]fluoren-5- one (0.810Kg, 75.0%th, 92.19% by HPLC area) as a purple solid. Stage 10: Preparation of l-cvclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH- benzoimidazol-2-vD- 1 H-pyrazol-4-yll -urea

C16H16N6O2 C19H23N7O2

FW: 324.34 FW: 381.44

As a mixture of two regioisomers

7-Morpholin-4-ylmethyl-254-dihydro-l,2,4,5a,10-pentaaza-cyclopenta[a]fluoren-5- one (0.797Kg, 2.46mol, l.Owt) and l-methyl-2-pyrrolidinone (2.40L, 3.0vol) were charged to a flange flask equipped with a mechanical stirrer, condenser and thermometer. Cyclopropylamine (0.279Kg, 4.88mol, 0.35 lwt) was added at 15 to 30°C under nitrogen. The contents were heated to 95 to 105°C and stirred at this temperature for 16 to 24 hours. Reaction completion was determined by1H NMR analysis. The reaction mixture was cooled to 10 to 200C and ethyl acetate (8.00L, lO.Ovol) and sat. aq. sodium chloride (2.50L, 3.0vol) were charged, the mixture was stirred for 2 to 5 minutes and the layers separated. The organic phase was stirred with sat. aq. sodium chloride (5.00L, ό.Ovol) for 25 to 35 minutes, the mixture filtered and the filter-cake washed with ethyl acetate (0.40L, 0.5vol). The filter-cake was retained and the filtrates were transferred to a separating funnel and the layers separated. The procedure was repeated a further 3 times and the retained solids were combined with the organic phase and the mixture concentrated to dryness under vacuum at 35 to 450C. The concentrate was dissolved in propan-2-ol (8.00L, lO.Ovol) at 45 to 55°C and activated carbon (0.080Kg5 O.lwt) was charged. The mixture was stirred at 45 to 550C for 30 to 40 minutes and then hot filtered at 45 to 55°C. The filter-cake was washed with propan-2-ol (0.40L, 0.5vol). Activated carbon (0.080L, O.lwt) was charged to the combined filtrates and wash and the mixture stirred at 45 to 550C for 30 to 40 minutes. The mixture was hot filtered at 45 to 550C and the filter-cake washed with propan-2-ol (0.40L, 0.5vol). The filtrates and wash were concentrated under vacuum at 35 to 450C. Ethyl acetate (8.00, lO.Ovol) and water (2.20L, 3.0vol) were charged to the concentrate at 25 to 350C and the mixture stirred for 1 to 2 minutes. The layers were separated and the organic phase was concentrated under vacuum at 35 to 45°C. Ethyl acetate (4.00L, 5.0vol) was charged to the residue and concentrated under vacuum at 35 to 450C. Ethyl acetate (4.00L, 5.0vol) was charged to the residue and the mixture was stirred for 2 to 20 hours at 15 to 250C. The mixture was cooled to and aged at 0 to 5°C for 90 to 120 minutes and then filtered. The filter-cake was washed with ethyl acetate (0.80L, l.Ovol) and pulled dry for 15 to 30 minutes. The solid was dried under vacuum at 35 to 450C to yield l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH- benzoimidazol-2-yl)-lH-pyrazol-4-yl]-urea (0.533Kg, 56.8%, 93.20% by HPLC area) as a brown solid.

Several batches of Stage 9 product were processed in this way and the details of the quantities of starting material and product for each batch are set out in Table IA.

Table IA – Yields from urea formation step – Stage 10

Stage 11 : Preparation of l-cyclopiOpyl-3-r3-(5-moipholin-4-ylmethyl-lH- benzoimidazol-2-yls)-lH-pyrazol-4-yll-urea £-lactic acid salt L-Lactic acid

acid

C19H23N7O2 C22H29N7O5

FW: 381.44 FW: 471.52 l-Cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol-2-yl)-lH-ρyrazol- 4-yl]-urea (1.859Kg, 4.872mol, l.Owt), propan-2-ol (9.00L5 5.0vol) and ethyl acetate (8.0OL, 4.5vol) were charged to a flange flask equipped with a mechanical stirrer and thermometer. The contents were stirred under nitrogen and L-lactic acid (0.504Kg, 5.59mol, 0.269wt) was added at 15 to 25°C followed by a line rinse of ethyl acetate (0.90L, 0.5vol). The mixture was stirred at 15 to 25°C for 120 to 140 minutes. The solid was isolated by filtration, the filter-cake washed with ethyl acetate (2x 2.00L, 2x l.Ovol) and pulled dry for 20 to 40 minutes. The filter-cake was dissolved in ethanol (33.00L, 17.7vol) at 75 to 850C, cooled to 65 to 700C and the solution clarified through glass microfibre paper. The filtrates were cooled to and aged at 15 to 250C for 2 to 3 hours. The crystallised solid was isolated by filtration, the filter-cake washed with ethanol (2x 1.00L, 2x 0.5vol) and pulled dry for at least 30 minutes. The solid was dried under vacuum at 35 to 45°C to yield 1- cyclopropyl-3 – [3-(5 -morpholin-4-ylmethyl- 1 H-benzoimidazol-2-yl)- 1 H-pyrazol-4- yl]-urea l-lactic acid salt (1.386Kg, 58.7%th, 99.47% by HPLC area,) as a dark pink uniform solid.

The infra-red spectrum of the lactate salt (KBr disc method) included characteristic peaks at 3229, 2972 and 1660 cm“1.

Without wishing to be bound by any theory, it is believed that the infra red peaks can be assigned to structural components of the salt as follow:

Peak: Due to:

3229 cm“1 N-H

2972 cm“1 aliphatic C-H

1660 cm“1 urea C=O EXAMPLE 67

Synthesis of Crystalline Free Base And Crystalline Salt Forms Of l-Cyclopropyl-3-

[3-(5-Morpholin-4-ylmethyl-lH-Benzoimidazol-2-vπ-lH-Pyrazol-4-yll-Urea

A. Preparation of l-Cvclopropyl-3-[3-f5-Moφholm-4-ylmethyl-lH- Benzoimidazol-2-yl)-lH-Pyrazol-4-yll-Urea free base

A sample of crude l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol- 2-yl)-lH-pyrazol-4-yl]-urea free base was prepared as outlined in Example 60 and initially purified by column chromatography on silica gel, eluting with EtOAc- MeOH (98:2 – 80:20). A sample of the free base obtained was then recrystallised from hot methanol to give crystalline material of l-cyclopropyl-3-[3-(5-morpholin- 4-ylmethyl- 1 H-benzoimidazol-2-yl)- 1 H-pyrazol-4-yl] -urea free base.

B. Preparation of l-Cyclopropyl-S-rS-fS-Morpholin^-ylmethyl-lH-Benzoimidazol- 2-yl)-lH-Pyrazol-4-yl]-Urea free base dihydrate

A sample of crude l-cyclopropyl-3-[3-(5-moφholm-4-ylmethyl-lH-benzoimidazol- 2-yl)-l H-pyrazol-4-yl] -urea free base was dissolved in THF and then concentrated in vacuo to a minimum volume (~4 volumes). To the solution was added water dropwise (2 – 4 volumes) until the solution became turbid. A small amount of THF was added to re-establish solution clarity and the mixture left to stand overnight to give a crystalline material which was air-dried to give l-cyclopropyl-3-[3-(5- morpholin-4-ylmethyl- 1 H-benzoimidazol-2-yl)- 1 H-pyrazol-4-yl] -urea free base dihydrate.

C. Preparation of l-Cyclopl^pyl-3-[3-(5-Morpholm-4-ylmethyl-lH-Benzoimidazol- 2-ylVlH-Pyrazol-4-yl]-Urea hydrochloride salt

A sample of crude l-cyclopropyl-3-[3-(5-moφholin-4-ylmethyl-lH-benzoimidazol- 2-yl)-l H-pyrazol-4-yl] -urea free base was dissolved in the minimum amount of MeOH and then diluted with EtOAc. To the solution at 0 °C was slowly added 1.1 equivalents of HCl (4M solution in dioxane). Following addition, solid precipitated from solution which was collected by filtration. To the solid was added MeOH and the mixture reduced in vacuo. To remove traces of residual MeOH the residue was evaporated from water and then dried at 60 0C/ 0.1 mbar to give the hydrochloride salt.

D. Preparation of l-Cyclopropyl-3-[3-(‘5-Morpholm-4-ylmethyl-lH- Benzoimidazol-2-yiyiH-Pyrazol-4-yl1-Urea ethanesulfonate salt

To a solution of l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol-2- yl)-lH-pyrazol-4-yl]-urea free base in MeOH-EtOAc was added 1 equivalent of ethanesulfonic acid. The mixture was stirred at ambient temperature and then reduced in vacuo. The residue was taken up in MeOH and to the solution was added Et2O. Mixture left to stand for 72 h and the solid formed collected by filtration and dried to give l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH- benzoimidazol-2-yl)-lH-pyrazol-4-yl]-urea ethanesulfonate salt.

E. Preparation of l-Cvclopropyl-3-[3-(‘5-Morpholm-4-ylmethyl-lH-Benzoimidazol- 2-yl)-lH-Pyrazol-4-yl]-Urea methanesulfonate salt

To a solution of l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol-2- yl)-lH-pyrazol-4-yl]-urea free base (394 mg) in MeOH-EtOAc was added 1 equivalent of methanesulfonic acid (67 μl). A solid was formed which was collected by filtration, washing with EtOAc. The solid was dissolved in the minimum amount of hot MeOH, allowed to cool and then triturated with Et2O. The solid was left to stand for 72 h and then collected by filtration, washing with MeOH, to give l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol-2- yl)-lH-pyrazol-4-yl]-urea methanesulfonate salt.

EXAMPLE 68

Characterisation of l-Cvclopropyl-3-[3-(5-Morpholin-4-ylmethyl-lH-

Benzoimidazol-2-yl)-lH-Pyrazol-4-yll-Urea Free Base and Salts

Various forms of l-cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-lH-benzoimidazol- 2-yl)-lH-pyrazol-4-yl]-urea were characterised. The forms selected for characterisation were identified from studies which primarily investigated extent of polymorphism and salt stability. The salts selected for further characterisation were the L-lactate salt, Free base dihydrate, Esylate salt, Free base and Hydrochloride salt.

Paper

Fragment-Based Discovery of the Pyrazol-4-yl Urea (AT9283), a Multitargeted Kinase Inhibitor with Potent Aurora Kinase Activity†

Steven Howard*, Valerio Berdini, John A. Boulstridge, Maria G. Carr, David M. Cross, Jayne Curry, Lindsay A. Devine, Theresa R. Early, Lynsey Fazal, Adrian L. Gill, Michelle Heathcote,Sarita Maman, Julia E. Matthews,Rachel L. McMenamin, Eva F. Navarro, Michael A. O’Brien,Marc O’Reilly, David C. Rees, Matthias Reule, Dominic Tisi, Glyn Williams, Mladen Vinković andPaul G. Wyatt

Astex Therapeutics Ltd., 436 Cambridge Science Park, Milton Road, Cambridge, CB4 0QA, U.K.

J. Med. Chem., 2009, 52 (2), pp 379–388

DOI: 10.1021/jm800984v

Publication Date (Web): December 30, 2008

Copyright © 2008 American Chemical Society

†

Coordinates of the protein complexes with compounds 5, 7, 9, 10, and 16 have been deposited in the Protein Data Bank under accession codes 2w1d, 2w1f, 2w1c, 2w1e, 2w1g (Aurora A),2w1h (CDK2), and 2w1i (JAK2).

, * To whom correspondence should be addressed. Phone: +44 (0)1223 226209. Fax: +44 (0)1223 226201. E-mail: s.howard@astex-therapeutics.com.

http://pubs.acs.org/doi/abs/10.1021/jm800984v

http://pubs.acs.org/doi/suppl/10.1021/jm800984v/suppl_file/jm800984v_si_001.pdf

Abstract

Here, we describe the identification of a clinical candidate via structure-based optimization of a ligand efficient pyrazole-benzimidazole fragment. Aurora kinases play a key role in the regulation of mitosis and in recent years have become attractive targets for the treatment of cancer. X-ray crystallographic structures were generated using a novel soakable form of Aurora A and were used to drive the optimization toward potent (IC50 ≈ 3 nM) dual Aurora A/Aurora B inhibitors. These compounds inhibited growth and survival of HCT116 cells and produced the polyploid cellular phenotype typically associated with Aurora B kinase inhibition. Optimization of cellular activity and physicochemical properties ultimately led to the identification of compound16(AT9283). In addition to Aurora A and Aurora B, compound 16 was also found to inhibit a number of other kinases including JAK2 and Abl (T315I). This compound demonstrated in vivo efficacy in mouse xenograft models and is currently under evaluation in phase I clinical trials.

1-Cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-1H-benzoimidazol-2-yl)-1H-pyrazol-4-yl]urea (16)

 16 as a pale-yellow solid (8.19 g, 87%). 1H NMR (400 MHz, Me-d3-OD): 8.07 (s, 1H), 7.58 (s, 2H), 7.26 (d, J = 8 Hz, 1H), 3.74−3.69 (m, 4H), 3.67 (s, 2H), 2.74−2.69 (m, 1H), 2.55−2.50 (m, 4H), 1.02−0.93 (m, 2H), 0.72−0.65 (m, 2H). LC/MS: tR = 1.08 min, m/z = 382 [M + H]+.

1-Cyclopropyl-3-[3-(5-morpholin-4-ylmethyl-1H-benzoimidazol-2-yl)-1H-pyrazol-4-yl]urea (16),Hydrochloride Salt

 1H NMR (400 MHz, DMSO-d6): 13.26−13.07 (m, 2H), 11.05−10.80 (m, 1H), 9.64 (s, 1H), 8.08 (s, 1H), 7.98−7.19 (4H, m), 4.44 (s, 2H), 3.94 (d, J = 12.4 Hz, 2H), 3.77 (t, J = 12.3 Hz, 2H), 3.28−3.20 (m, 2H), 3.17−3.05 (m, 2H), 2.65−2.57 (m, 1H), 0.96−0.79 (m, 2H), 0.63−0.51 (m, 2H).

Reference:

[1] J Med. Chem. 2009, 52, 379-388………http://pubs.acs.org/doi/pdf/10.1021/jm800984v

[2] Cell Cycle 2009, 8, 1921-1929.

[US2014336073]

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