IPI 504, Retaspamycin, Retaspimycin

IPI 504, Retaspamycin, Retaspimycin
CAS 857402-63-2
Cas 857402-23-4 ( Retaspimycin); 857402-63-2 ( Retaspimycin  HCl).

MF C31H45N3O8 BASE

MW: 587.32067 BASE

Infinity Pharmaceuticals Inc,  INNOVATOR

[(3R,5S,6R,7S,8E,10S,11S,12Z,14E)-6,20,22-trihydroxy-5,11-dimethoxy-3,7,9,15-tetramethyl-16-oxo-21-(prop-2-enylamino)-17-azabicyclo[16.3.1]docosa-1(22),8,12,14,18,20-hexaen-10-yl] carbamate;hydrochloride
17-Allylamino-17-demethoxygeldanamycin Hydroquinone Hydrochloride

1. UNII-928Q33Q049
2. SEE.........http://www.biotechduediligence.com/retaspamycin-hcl-ipi-504.html

Retaspimycin hydrochloride; 8,21-didehydro-17-demethoxy-18,21-dideoxo-18,21-dihydroxy-17-(2-propenylamino)-geldanamycin monohydrochloride
Application:	A novel, water-soluble, potent inhibitor of heat-shock protein 90 (Hsp90)
Molecular Weight:	624.17 ..........HCl salt
Molecular Formula:	C31H46ClN3O8..........HCl salt

Introduction

IPI-504 is a novel, water-soluble, potent inhibitor of heat-shock protein 90 (Hsp90).
Orphan drug designation was assigned to the compound by the FDA for the treatment of gastrointestinal stromal cancer (GIST).

Retaspimycin Hydrochloride is the hydrochloride salt of a small-molecule inhibitor of heat shock protein 90 (HSP90) with antiproliferative and antineoplastic activities. Retaspimycinbinds to and inhibits the cytosolic chaperone functions of HSP90, which maintains the stability and functional shape of many oncogenic signaling proteins and may be overexpressed or overactive in tumor cells. Retaspimycin-mediated inhibition of HSP90 promotes the proteasomal degradation of oncogenic signaling proteins in susceptible tumor cell populations, which may result in the induction of apoptosis.
Phase I study of Retaspimycin: A phase 1 study of IPI-504 (retaspimycin hydrochloride) administered intravenously twice weekly for 2 weeks at 22.5, 45, 90, 150, 225, 300 or 400 mg/m(2) followed by 10 days off-treatment was conducted to determine the safety and maximum tolerated dose (MTD) of IPI-504 in patients with relapsed or relapsed/refractory multiple myeloma (MM). Anti-tumor activity and pharmacokinetics were also evaluated. Eighteen patients (mean age 60.5 years; median 9 prior therapies) were enrolled. No dose-limiting toxicities (DLTs) were reported for IPI-504 doses up to 400 mg/m(2).
The most common treatment-related adverse event was grade 1 infusion site pain (four patients). All other treatment-related events were assessed as grade 1 or 2 in severity. The area under the curve (AUC) increased with increasing dose, and the mean half-life was approximately 2-4 h for IPI-504 and its metabolites. Four patients had stable disease, demonstrating modest single-agent activity in relapsed or relapsed/refractory MM.  (source: Leuk Lymphoma. 2011 Dec;52(12):2308-15.)

Figure Hsp90 protein partners and clients destabilized by Hsp90 inhibition (Jackson et al., 2004).

In a different approach, Infinity Pharmaceuticals has developed IPI504 (retaspimycin or 17-AAG hydroquinone, Figure 4) (Adams et al., 2005; Sydor et al., 2006), a new GA analogue, in which the quinone moiety was replaced by a dihydroquinone one. Indeed, the preclinical data suggested that the hepatotoxicity of 17-AAG was attributable to the ansamycin benzoquinone moiety, prone to nucleophilic attack.

Furthermore, it was recently reported that the hydroquinone form binds Hsp90 with more efficiency than the corresponding quinone form (Maroney et al., 2006). In biological conditions, the hydroquinone form can interconvert with GA, depending on redox equilibrium existing in cell. It has been recently proposed, that NQ01 (NAD(P)H: quinone oxidoreductase) can produce the active hydroquinone from the quinone form of IPI504 (Chiosis, 2006).

However, Infinity Pharmaceuticals showed that if the overexpression of NQ01 increased the level of hydroquinone and cell sensitivity to IPI504, it has no significant effect on its growth inhibitory activity. These results suggest that NQ01 is not a determinant of IPI504 activity in vivo (Douglas et al., 2009).

Figure 4: GA, 17-AAG, 17-DMAG and IPI504.

PATENT

http://www.google.com/patents/EP2321645A1?cl=en
Geldanamycin (IUPAC name ([18S-(4E,5Z,8R*.9R*.10E,12R*.13S*,14R*,l6S*)]- 9- [(aminocarbonyl)oxy]- 13- hydroxy- 8,14,19- trimetoxy- 4,10,12,16- tetramethyl- 2- azabicyclo[16.3.1.]docosa- 4,6.10,18,21- pentan- 3.20,22trion) is a benzoquinone ansamycin antibiotic which may be produced by the bacterium Streptorayces hygroscopicus. Geldanamycin binds specifically to HSP90 (Heat Shock Protein 90) and alters its function.
While Hsp90 generally stabilizes folding of proteins and, in particular in tumor cells, folding of overexpressed/mutant proteins such as v-Src. Bcr-Abl and p53. the Hsp90 inhibitor Geldanamycin induces degradation of such proteins.
The respectiv e formula of geldanamycin is given herein below:

E\en though geldanamycin is a potent antitumor agent, the use of geldanamycin also shows some negathe side-effects (e.g. hepatotoxicity) which led to the dev elopment of geldanamycin analogues/derivatives, in particular analogues/deriv atives containing a derivatisation at the 17 position. Without being bound by theory , modification at the 17 position of geldanamycin may lead to decreases hepatotoxicity.
Accordingly geldanamycin analogues/derivatives which are modified at the 17 position, such as 17-AAG (17-N-Allylamino-17-demethoxygeldanamycin), are preferred in context of the present invention. Also preferred herein are geldanamycin derivatives to be used in accordance with the present invention which are water-soluble or which can be dissoh ed in water completely (at least 90 %. more preferably 95 %. 96 %. 97 %, 98 % and most preferably 99 %). 17-AAG ([QS.5S,6RJS$EΛ0R,l \SΛ2E,14E)-2\- (allylamino)-6-hydroxy-5.11-diraethoxy-
3.7.9,15-tetramethyl-16.20.22-trioxo-17-azabicyclo[16.3.1]docosa-8,12.14,18,21-pentaen-10- yl] carbamate) is. as mentioned above a preferred derivative of geldanamycin. 17- AAG is commercially available under the trade name "Tanespimycin^" (also known as KOS-953) for example from Kosan Biosciences Incorporated (Acquired by Bristol-Myers Squibb Company). Tanespimycin is presently studied in phase II clinical trials for multiple myeloma and breast cancer and is usually administered intravenously.
The respective formula of 17- AAG is given herein below:

Preferred geldanamycin-derh ative (HSP90 inhibitor) to be used in context of the present invention are IPI-504 (also known as retaspiimcin or Mcdi-561 : lnfinin Pharmaceuticals (Medlmmunc/ Astra Zeneca)). Clinical trials on the use of IPI-504 (which is usually administered intravenously) in the treatment of non-small cell lung cancer (NSCLC) and breast cancer are performed. Also alvespimycin hy drochloride (Kosan Biosciences Incorporated Acquired By : Bristol-Myers Squibb Company) is a highly potent, water-soluble and orally acti\e derivative of geldanamycin preferably used in context of the present invention.

IPI-504

PATENT

WO 2005063714
http://www.google.co.ug/patents/WO2005063714A1?cl=en
Example 24
Preparation of Air-stable Hydroquinone Derivatives of the Geldanamycin Family of Molecules
,

17-Allylamino-17-Demethoxygeldanamycin (10.0 g, 17.1 mmol) in ethyl acetate
(200 mL) was stirred vigorously with a freshly prepared solution of 10% aqueous sodium hydrosulfite (200 mL) for 2 h at ambient temperature. The color changed from dark purple to bright yellow, indicating a complete reaction. The layers were separated and the organic phase was dried with magnesium sulfate (15 g). The drying agent was rinsed with ethyl acetate (50 mL). The combined filtrate was acidified with 1.5 M hydrogen chloride in ethyl acetate (12 mL) to pH 2 over 20 min. The resulting slurry was stirred for 1.5 h at ambient temperature. The solids were isolated by filtration, rinsed with ethyl acetate (50 mL) and dried at 40 °C, 1 mm Hg, for 16 h to afford 9.9 g (91%) of off-white solid. Crude hydroquinone hydrochloride (2.5 g) was added to a stirred solution of 5% 0.01 N aq. hydrochloric acid in methanol (5 mL). The resulting solution was clarified by filtration then diluted with acetone (70 mL). Solids appeared after 2-3 min. The resulting slurry was stirred for 3 h at ambient temperature, then for 1 h at 0-5 °C. The solids were isolated by filtration, rinsed with acetone (15 mL) and dried

PAPER

J. Med. Chem., 2006, 49 (15), pp 4606–4615

DOI: 10.1021/jm0603116

http://pubs.acs.org/doi/abs/10.1021/jm0603116

17-Allylamino-17-demethoxygeldanamycin (17-AAG)¹ is a semisynthetic inhibitor of the 90 kDa heat shock protein (Hsp90) currently in clinical trials for the treatment of cancer. However, 17-AAG faces challenging formulation issues due to its poor solubility. Here we report the synthesis and evaluation of a highly soluble hydroquinone hydrochloride derivative of 17-AAG, 1a (IPI-504), and several of the physiological metabolites. These compounds show comparable binding affinity to human Hsp90 and its endoplasmic reticulum (ER) homologue, the 94 kDa glucose regulated protein (Grp94). Furthermore, the compounds inhibit the growth of the human cancer cell lines SKBR3 and SKOV3, which overexpress Hsp90 client protein Her2, and cause down-regulation of Her2 as well as induction of Hsp70 consistent with Hsp90 inhibition. There is a clear correlation between the measured binding affinity of the compounds and their cellular activities. Upon the basis of its potent activity against Hsp90 and a significant improvement in solubility, 1a is currently under evaluation in Phase I clinical trials for cancer.

17-Allylamino-17-demethoxygeldanamycin Hydroquinone Hydrochloride Ia

17-AAG hydroquinone hydrochloride (1a) as an off-white solid (11 g, 18 mmol, 80% yield). HPLC purity:  99.6%;
IR (neat):  3175, 2972, 1728, 1651, 1581, 1546, 1456, 1392, 1316, 1224, 1099, 1036 cm^-1;
¹H NMR (CDCl₃:d₆-DMSO, 6:1, 400 MHz): 
δ 10.20 (1H, br), 9.62 (2H, br), 8.53 (1H, s), 8.47 (1H, s), 7.74 (1H, s), 6.72 (1H, d, J= 11.6 Hz), 6.28 (1H, dd, J = 11.6, 11.2 Hz), 5.73 (1H, dddd, J = 17.2, 10.0, 3.2, 2.4 Hz), 5.53 (1H, d, J = 10.4 Hz), 5.49 (1H, dd, J = 10.8, 10.0 Hz), 5.32 (2H, s), 5.04 (1H, d, J = 4.8 Hz), 5.02 (1H, d, J = 16.0 Hz), 4.81 (1H, s), 4.07 (1H, d, J = 9.6 Hz), 3.67 (2H, d, J = 6.4 Hz), 3.31 (1H, d,J = 8.8 Hz), 3.07 (3H, s), 3.07−3.04 (1H, m), 2.99 (3H, s), 2.64 (1H, m), 2.52−2.49 (1H, m), 1.76 (3H, s), 1.61−1.39 (3H, m), 0.78 (3H, d, J = 6.4 Hz), 0.64 (3H, d, J = 7.2 Hz);
¹³C NMR (CDCl₃:d₆-DMSO, 6:1, 100 MHz):  δ 167.3, 155.8, 143.3, 136.3, 135.0, 134.2, 132.9, 132.1, 128.8, 127.6, 125.9, 125.3, 123.7, 123.0, 115.1, 104.5, 80.9, 80.7, 80.1, 72.5, 56.2, 56.2, 52.4, 34.6, 33.2, 31.1, 27.2, 21.6, 12.1, 12.1, 11.7;
HRMS calculated for C₃₁H₄₅N₃O₈ (M⁺ + H):  588.3285, Found 588.3273.

POSTER

Synthesis and biological evaluation of IPI-504, an aqueous soluble analog of 17-AAG and potent inhibitor of Hsp90

MEDI 210

James R. Porter, jporter@ipi.com, Jie Ge, Emmanuel Normant, Janid Ali, Marlene S. Dembski, Yun Gao, Asimina T. Georges, Louis Grenier, Roger Pak, Jon Patterson, Jens R. Sydor, Jim Wright, Julian Adams, and Jeffrey K. Tong.   Infinity Pharmaceuticals, Inc, 780 Memorial Drive, Cambridge, MA 02139

IPI-504 is the hydroquinone hydrochloride salt of 17-allylamino-17-demethoxy-geldanamycin (17-AAG), an Hsp90 inhibitor that is currently in clinical trials for the treatment of cancer. IPI-504 demonstrates high aqueous solubility (>200 mg/mL). Interestingly, in vitro and in vivo IPI-504 interconverts with 17-AAG and exists in a pH and enzyme-mediated redox equilibrium. This occurs due to oxidation of the hydroquinone (IPI-504) to the quinone (17-AAG) at physiological pH and the reduction of 17-AAG by quinone reductases such as NQO1 to IPI-504. Here we report the design and synthesis of the stabilized hydroquinone IPI-504 and its inhibitory effect against Hsp90 and Grp94. Although IPI-504 was originally designed to be a soluble prodrug of 17-AAG, the hydroquinone is more potent than the quinone in the biochemical Hsp90 binding assay. Various hydroquinone analogs have been prepared to investigate the structure activity relationship of hydroquinone binding to Hsp90. Hydroquinone and quinone forms of 17-AAG metabolites show comparable binding affinities for Hsp90 and in cancer cell lines, hydroquinone analogs elicit specific responses consistent with Hsp90 inhibition. The desirable pharmacological properties as well as in vitro and in vivo activity of our lead compound, IPI-504, has led to the initiation of Phase I clinical trials in multiple myeloma.

http://oasys2.confex.com/acs/231nm/techprogram/P945016.HTM

Geldanamycin and Beyond: Progress Toward the Development of HSP90 Inhibitors 8:30 AM-12:05 PM, Wednesday, 29 March 2006 Georgia World Congress Center -- Georgia Ballroom 1, OralDivision of Medicinal ChemistryThe 231st ACS National Meeting, Atlanta, GA, March 26-30, 2006

References

Synthesis and biological evaluation of IPI-504, an aqueous soluble analog of 17-AAG and potent inhibitor of Hsp90
231st Am Chem Soc (ACS) Natl Meet (March 26-30, Atlanta) 2006, Abst MEDI 210
Design, synthesis, and biological evaluation of hydroquinone derivatives of 17-amino-17-demethoxygeldanamycin as potent, water-soluble inhibitors of Hsp90
J Med Chem 2006, 49(15): 4606
http://www.biotechduediligence.com/retaspamycin-hcl-ipi-504.html
///////////////////Hsp90, IPI-504, infinity pharma, Retaspamycin, Retaspimycin

IPI 926, Saridegib, Patidegib

IPI 926, Saridegib, Patidegib

C29H48N2O3S

Exact Mass: 504.33856

1037210-93-7

• Patidegib hydrochloride
• Saridegib hydrochloride
• • C29-H48-N2-O3-S.Cl-H

  • 541.2361

http://chem.sis.nlm.nih.gov/chemidplus/rn/1169829-40-6

Methanesulfonamide, N-((2S,3R,3'R,3aS,4'aR,6S,6'aR,6'bS,7aR,12'aS,12'bS)-2',3',3a,4,4',4'a,5,5',6,6',6'a,6'b,7,7',7a,8',10',12',12'a,12'b-eicosahydro-3,6,11',12'b-tetramethylspiro(furo(3,2-b)pyridine-2(3H),9'(1'H)-naphth(2,1-a)azulen)-3'-yl)-, hydrochloride (1:1)

 CAS 1169829-40-6 HCL

Saridegib also known as IPI-926 is an experimental drug candidate undergoing clinical trials for the treatment of various types of cancer, including hard to treat hematologic malignancies such as myelofibrosis and ligand-dependant tumors such as chondrosarcoma.^[1] IPI-926 exhibits its pharmacological effect by inhibition of the G protein-coupled receptor smoothened, a component of the hedgehog signaling pathway.^[2]
Chemically, it is a semi-synthetic derivative of the alkaloid cyclopamine. The process begins with cyclopamine extracted from harvested Veratrum californicum which is taken through a series of alterations resulting in an analogue of the natural product cyclopamine, making IPI-926 the only compound in development/testing that is not fully synthetic.^[2]

Saridegib is a member of a class of anti-cancer compounds known as hedgehog inhibitors (Hhi). Most of these compounds affect thehedgehog signaling pathway via inhibition of smoothened (Smo), a key component of the pathway. Depending on when a Hh inhibiting compound is approved by the U.S. Food and Drug Administration (FDA), there may be a perceived need for one to be differentiated over another for marketing purposes, which could lead to different nomenclature (e.g., a Hhi or an agonist of Smo).
This marketing technique is more of a differentiation strategy than a scientific property of these compounds, as the mechanism of action (MOA) in the end is inhibition of the Hh pathway, targeting cancer stem cells. However, as these new compounds are further studied, identification of differences in a compound's MOA, could lead to hypotheses regarding the stage at which Smo is inhibited, where along the pathway the compound binds, or specific binding properties of a compound.
If these hypotheses are proven, claims could be made regarding a specific compound's MOA and how it affects efficacy, safety, combinability with other cancer treatments, etc. Scientific data in support of such hypotheses have not been published to date.

SARIDEGIB

N-[(3R,3'R,3'aS,4aR,6'S,6aR,6bS,7'aR,9S,12aS,12bS)-3',6',11,12b-tetramethylspiro[1,2,3,4,4a,5,6,6a,6b,7,8,10,12,12a-tetradecahydronaphtho[2,1-a]azulene-9,2'-3a,4,5,6,7,7a-hexahydro-3H-furo[3,2-b]pyridine]-3-yl]methanesulfonamide

There are currently no drugs in the Hhi class FDA approved, however IPI-926 and GDC-0449 are the 2 leading compounds in the class. IPI-926, GDC-0449, and LDE-225 are the only compounds that have generic names passed by the United States Adopted Name (USAN) council (Infinity IPI-926/saridegib, Genentech GDC-0449/vismodegib, and Novartis LDE-225/erismodegib). Although Infinity is further along in chondrosarcoma, myelofibrosis, and AML, Roche/Genentech recently submitted an NDA for GDC-0449 for the treatment of adults with advanced basal cell carcinoma (BCC) when surgery is no longer an option, and the FDA has accepted and has filed the NDA, giving it priority review status. Thus it appears that Roche/Genentech will be the first Hhi to market with GDC-0449, if approved, for the treatment of advanced BCC, with Infinity second to market with IPI-926 for treatment in chondrosarcoma. It appears Infinity will not pursue an indication for BCC and focus on cancers with high unmet needs.^{[1][3][4][5][6]}
Other Hhi-class compounds not as far along in development as IPI-926 and GDC-0449 include:^[7]

• Novartis' LDE-225 (USAN generic name erismodegib)
• Exelixis/Bristol-Myers Squibb's BMS-833923 (XL139)
• Millennium Pharmaceuticals's TAK-441
• Pfizer's PF-04449913

 

Fig 1. Chemical structure comparison between IPI-926 and cyclopamine

IPI-926 is currently developed by Infinity Pharmaceuticals, Inc. Malignant activation of the Hedgehog pathway is implicated in multiple cancer settings and Infinity's development strategy is designed to enable IPI-926 to target a broad range of critical oncology targets - from the tumor cell to the cancer microenvironment. This broadly applicable, targeted approach represents an innovative method for fighting cancer and has potential in treating a range of cancers, including pancreatic cancer, small cell lung cancer, ovarian cancer, bladder cancer, medulloblastoma, basal cell carcinoma, and certain hematological malignancies.

The hedgehog pathway inhibitor IPI-926 has been in clinical investigation for basal cell carcinoma, chondrosarcoma, and pancreatic cancer. In the final step of the synthesis of IPI-926  the drug substance (DS) is isolated as the hydrochloride salt of the 2-propanol (2-PrOH) solvate

A design of experiments (DoE) approach was taken to optimize purity and reaction yield of the final debenzylation and hydrochloride salt formation of IPI-926. The study involved a careful dissection of the different process steps to enable an independent investigation of these steps while ensuring that process streams were representative. The results enabled a streamlined process from the final chemical transformation to the salting and isolation and led to the elimination of variability in the process as well as a robust control of impurities. The optimized process was applied to production and demonstrated on the kilogram scale.

A Design of Experiments Approach to a Robust Final Deprotection and Reactive Crystallization of IPI-926, A Novel Hedgehog Pathway Inhibitor

Theodore A. Martinot^*, Brian C. Austad, Alexandre Côté, Kristopher M. Depew, Daniel Genov, Louis Grenier, Joseph Helble, Andre Lescarbeau, Somarajan Nair, Martin Trudeau, Priscilla White, andLin-Chen Yu

Infinity Pharmaceuticals, 784 Memorial Drive, Cambridge, Massachusetts 02139, United States

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00214

http://pubs.acs.org/doi/full/10.1021/acs.oprd.5b00214

The product was dried at a jacket temperature of 45 °C until an LOD <2.30% (w/w) was achieved. Yield: 11.5 kg (73% from compound 1, correcting for the seed). HPLC purity: 99.9% area (compound 2 content: 0.08% w/w). Assay: 83.7% w/w (as-is), 99.1% w/w (anhydrous, solvent-free). Moisture content: 1.6% w/w. Chlorine content: 5.72% w/w. Residual solvents: acetone (720 ppm); acetonitrile (<41 ppm); 2-MeTHF (none detected); 2-propanol (81 147 ppm); toluene (<90 ppm). Residual metals: palladium (0 ppm); platinum (0 ppm); ruthenium (0 ppm). Additional data for the IPI-926 free base:
¹H NMR (400 MHz, CDCl₃) 6.90 (br s, 1H), 3.31 (dt, J = 10.6, 3.8 Hz, 1H), 3.20 (br s, 1H), 3.10 (dd, J = 13.7, 4.5 Hz, 1H), 2.91 (s, 3H), 2.62 (dd,J = 9.9, 7.6 Hz, 1H), 2.33 (br d, J = 14.5 Hz, 1H), 2.27–2.15 (m, 1H), 2.10 (dd, J = 14.5, 6.9 Hz, 1H), 1.99–1.17 (m, 28H), 1.05 (q, J = 11.6 Hz, 1H), 0.93 (d, J = 7.4 Hz, 3H), 0.88 (d, J = 6.6 Hz, 3H), 0.86 (s, 3H) ppm.
¹³C NMR (100 MHz, CDCl₃) 140.47, 124.53, 82.48, 76.97, 63.73, 54.08, 53.87, 50.12, 49.98, 47.19, 44.73, 42.27, 42.10, 40.24, 37.55, 37.44, 36.04, 34.44, 31.87, 31.33, 30.46, 29.79, 28.37, 27.94, 26.26, 24.19, 22.70, 18.92, 10.19 ppm;
MS: m/z = 505.29 [M + H]⁺.
PAPER
Tremblay, M. R.; Lescarbeau, A.; Grogan, M. J.; Tan, E.; Lin, G.; Austad, B. C.; Yu, L.-C.;Behnke, M. L.; Nair, S. J.; Hagel, M.; White, K.; Conley, J.; Manna, J. D.; Alvarez-Diez, T. M.; Hoyt, J.; Woodward, C. N.; Sydor, J. R.; Pink, M.; MacDougall, J.; Campbell, M. J.;Cushing, J.; Ferguson, J.; Curtis, M. S.; McGovern, K.; Read, M. A.; Palombella, V. J.;Adams, J.; Castro, A. C. J. Med. Chem. 2009, 52, 4400– 4418, DOI: 10.1021/jm900305z

J. Med. Chem., 2009, 52 (14), pp 4400–4418

DOI: 10.1021/jm900305z

http://pubs.acs.org/doi/abs/10.1021/jm900305z

Recent evidence suggests that blocking aberrant hedgehog pathway signaling may be a promising therapeutic strategy for the treatment of several types of cancer. Cyclopamine, a plant Veratrum alkaloid, is a natural product antagonist of the hedgehog pathway. In a previous report, a seven-membered D-ring semisynthetic analogue of cyclopamine, IPI-269609 (2), was shown to have greater acid stability and better aqueous solubility compared to cyclopamine. Further modifications of the A-ring system generated three series of analogues with improved potency and/or solubility. Lead compounds from each series were characterized in vitro and evaluated in vivo for biological activity and pharmacokinetic properties. These studies led to the discovery of IPI-926 (compound 28), a novel semisynthetic cyclopamine analogue with substantially improved pharmaceutical properties and potency and a favorable pharmacokinetic profile relative to cyclopamine and compound2. As a result, complete tumor regression was observed in a Hh-dependent medulloblastoma allograft model after daily oral administration of 40 mg/kg of compound 28.

28 (4.06 g, 8.05 mmol, 95% for two steps). NMR δ_H (400 MHz, CDCl₃) 6.90 (br s, 1H), 3.31 (dt, J = 10.6, 3.8 Hz, 1H), 3.20 (br s, 1H), 3.10 (dd, J = 13.7, 4.5 Hz, 1H), 2.91 (s, 3H), 2.62 (dd, J = 9.9, 7.6 Hz, 1H), 2.33 (br d, J = 14.5 Hz, 1H), 2.27−2.15 (m, 1H), 2.10 (dd, J = 14.5, 6.9 Hz, 1H), 1.99−1.17 (m, 28H), 1.05 (q, J = 11.6 Hz, 1H), 0.93 (d, J = 7.4 Hz, 3H), 0.88 (d, J = 6.6 Hz, 3H), 0.86 (s, 3H); NMR δ_C (100 MHz, CDCl₃) 140.47, 124.53, 82.48, 76.97, 63.73, 54.08, 53.87, 50.12, 49.98, 47.19, 44.73, 42.27, 42.10, 40.24, 37.55, 37.44, 36.04, 34.44, 31.87, 31.33, 30.46, 29.79, 28.37, 27.94, 26.26, 24.19, 22.70, 18.92, 10.19; m/z = 505.29 [M + H]⁺; HPLC 99.1 a/a % at 215 nm.

Click on images for clear view.................

 

 

 

Paper

A design of experiments (DoE) approach was taken to optimize purity and reaction yield of the final debenzylation and hydrochloride salt formation of IPI-926. The study involved a careful dissection of the different process steps to enable an independent investigation of these steps while ensuring that process streams were representative. The results enabled a streamlined process from the final chemical transformation to the salting and isolation and led to the elimination of variability in the process as well as a robust control of impurities. The optimized process was applied to production and demonstrated on the kilogram scale.

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00214..........http://pubs.acs.org/doi/abs/10.1021/acs.oprd.5b00214

http://pubs.acs.org/doi/suppl/10.1021/acs.oprd.5b00214/suppl_file/op5b00214_si_001.pdf

 IPI-926 free base:

¹H NMR (400 MHz, CDCl₃) 6.90 (br s, 1H), 3.31 (dt, J = 10.6, 3.8 Hz, 1H), 3.20 (br s, 1H), 3.10 (dd, J = 13.7, 4.5 Hz, 1H), 2.91 (s, 3H), 2.62 (dd,J = 9.9, 7.6 Hz, 1H), 2.33 (br d, J = 14.5 Hz, 1H), 2.27–2.15 (m, 1H), 2.10 (dd, J = 14.5, 6.9 Hz, 1H), 1.99–1.17 (m, 28H), 1.05 (q, J = 11.6 Hz, 1H), 0.93 (d, J = 7.4 Hz, 3H), 0.88 (d, J = 6.6 Hz, 3H), 0.86 (s, 3H) ppm.

¹³C NMR (100 MHz, CDCl₃) 140.47, 124.53, 82.48, 76.97, 63.73, 54.08, 53.87, 50.12, 49.98, 47.19, 44.73, 42.27, 42.10, 40.24, 37.55, 37.44, 36.04, 34.44, 31.87, 31.33, 30.46, 29.79, 28.37, 27.94, 26.26, 24.19, 22.70, 18.92, 10.19 ppm;

MS: m/z = 505.29 [M + H]⁺.

References

1.  "Pipeline: IPI-926". Infinity Pharmaceuticals.
2.  Tremblay, MR; Lescarbeau, A; Grogan, MJ; Tan, E; Lin, G; Austad, BC; Yu, LC; Behnke, ML et al. (2009). "Discovery of a potent and orally active hedgehog pathway antagonist (IPI-926)". Journal of Medical Chemistry 52 (14): 4400–18. doi:10.1021/jm900305z. PMID 19522463.
3.  "Pipeline". Infinity Pharmaceuticals.
4.  "Genentech Pipeline". Genentech.
5.  "USAN Stem List" (PDF). AMA.
6.  "Names under consideration". AMA.
7.  "Search results for Hh clinical trials". United National Institute of Health's ClinicalTrials.gov.
8. 1. Tremblay MR, Lescarbeau A, Grogan MJ, Tan E, Lin G, Austad BC, Yu LC, Behnke ML, Nair SJ, Hagel M et al.. (2009)
   Discovery of a potent and orally active hedgehog pathway antagonist (IPI-926).
   J. Med. Chem., 52 (14): 4400-18.

Saridegib

Names
IUPAC name N-((2S,3R,3aS,3′R,4a′R,6S,6a′R,6b′S,7aR,12a&prmie;S,12b′S)-3,6,11′,12b′-tetramethyl-2′,3a,3′,4,4′,4a′,5,5&prmie;,6,6′,6a′,6b′,7,7a,7′,8′,10′,12′,12a′,12b′-icosahydro-1′H,3H-spiro[furo[3,2-b]pyridine-2,9'-naphtho[2,1-a]azulen]-3'-yl)methanesulfonamide
Other names saridegib
Identifiers
CAS Registry Number	1037210-93-7
ChEMBL	ChEMBL538867
ChemSpider	26353073
IUPHAR/BPS	8198
Jmol-3D images	Image
PubChem	25027363
SMILES[show]
UNII	JT96FPU35X
Properties
Chemical formula	C29H48N2O3S
Molar mass	504.77 g·mol−1
Pharmacology
Legal status	Investigational

/////Saridegib, IPI-926

Synthesis of a fluorinated Ezetimibe analogue

Synthesis of a fluorinated Ezetimibe analogue using radical allylation of [small alpha]-bromo-[small alpha]-fluoro-[small beta]-lactam

New J. Chem., 2015, Advance Article
DOI: 10.1039/C5NJ01969A, Paper

Atsushi Tarui, Ayumi Tanaka, Masakazu Ueo, Kazuyuki Sato, Masaaki Omote, Akira Ando

Atsushi Tarui,^a   Ayumi Tanaka,^a   Masakazu Ueo,^a  Kazuyuki Sato,^a   Masaaki Omote^a and   Akira Ando*^a  

 

*Corresponding authors

^aFaculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Japan
E-mail: aando@pharm.setsunan.ac.jp

A facile and efficient synthesis of a fluorinated Ezetimibe analogue was achieved by radical allylation, Wacker oxidation, and nucleophilic arylation of [small alpha]-bromo-[small alpha]-fluoro-[small beta]-lactam

The synthesis of an α-fluoro-β-lactam-containing Ezetimibe analogue was accomplished starting from α-bromo-α-fluoro-β-lactam which was readily prepared from ethyl dibromofluoroacetate. A facile and efficient method for the introduction of the C3 alkyl side chain was realized via radical allylation. The diastereoselective allylation of α-bromo-α-fluoro-β-lactam was successfully applied to construct the relative configuration of the β-lactam nucleus between C3 and C4. Further modification of the allyl side chain gave the 3′-(4-fluorophenyl)-3′-hydroxypropyl group through Wacker oxidation and nucleophilic arylation.
http://pubs.rsc.org/en/Content/ArticleLanding/2015/NJ/C5NJ01969A?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FNJ+%28RSC+-+New+J.+Chem.+latest+articles%29#!divAbstract

Sparsentan, PS433540, RE-021

  

Sparsentan(PS433540,RE-021)

• C₃₂H₄₀N₄O₅S
• Average mass592.749

4'-((2-butyl-4-oxo-1,3-diazaspiro[4.4]non-1-en-3-yl)methyl)-N-(4,5-dimethylisoxazol-3-yl)-2'-(ethoxymethyl)-[1,1'-biphenyl]-2-sulfonamide 

4'-[(2-Butyl-4-oxo-1.3-diazaspiro[4.41non-l-en-3-yl)methvn-N-(3,4- dimethyl-5-isoxazolyl)-2'-ethoxymethyl [ 1 , l'-biphenyll -2-sulfonamide

Sparsentan
PS433540; RE-021, formerly known as DARA
CAS :254740-64-2
4-[(2-butyl-4-oxo-1,3-diazaspiro[4.4]non-1-en-3-yl)methyl]-N-(4,5- dimethylisoxazol-3-yl)-2-(ethoxymethyl)biphenyl-2-sulfonamide
Mechanism of Action:acting as both an Endothelin Receptor Antagonist (ERA) and Angiotensin Receptor Blocker (ARB).
Indication: Focal Segmental Glomerulosclerosis (FSGS).Focal Segmental Glomerulosclerosis (FSGS) is a rare and severe nephropathy which affects approximately 50,000 patients in the United States. Most cases of FSGS are pediatric.
Development Stage: Phase II
Developer:Retrophin, Inc

• OriginatorBristol-Myers Squibb
• DeveloperRetrophin
• ClassAntihypertensives; Isoxazoles; Small molecules; Spiro compounds; Sulfonamides
• Mechanism of ActionAngiotensin type 1 receptor antagonists; Endothelin A receptor antagonists
• Orphan Drug Status Yes - Focal segmental glomerulosclerosis
• • 09 Jan 2015 Sparsentan receives Orphan Drug status for Focal segmental glomerulosclerosis in USA
  • 31 Dec 2013 Phase-II/III clinical trials in Focal segmental glomerulosclerosis in USA (PO)
  • 07 May 2012I nvestigation in Focal segmental glomerulosclerosis in USA (PO)

Sparsentan is an investigational therapeutic agent which acts as both a selective endothelin receptor antagonist and an angiotensin receptor blocker. Retrophin is conducting the Phase 2 DUET trial of Sparsentan for the treatment of FSGS, a rare and severe nephropathy that is a leading cause of end-stage renal disease. There are currently no therapies approved for the treatment of FSGS in the United States. Ligand licensed worldwide rights of Sparsentan (RE-021) to Retrophin in 2012 .The Food and Drug Administration (FDA) has granted orphan drug designation for Retrophins sparsentan for the treatment of focal segmental glomerulosclerosis (FSGS) in January 2015.
In 2006, the drug candidate was licensed to Pharmacopeia by Bristol-Myers Squibb for worldwide development and commercialization. In 2012, a license was obtained by Retrophin from Ligand. In 2015, Orphan Drug Designation was assigned by the FDA for the treatment of focal segmental glomerulosclerosis.
Sparsentan, also known as RE-021, BMS346567, PS433540 and DARA-a, is a Dual angiotensin II and endothelin A receptor antagonist. Retrophin intends to develop RE-021 for orphan indications of severe kidney diseases including Focal Segmental Glomerulosclerosis (FSGS) as well as conduct proof-of-concept studies in resistant hypertension and diabetic nephropathy. RE-021, with its unique dual blockade of angiotensin and endothelin receptors, is expected to provide meaningful clinical benefits in mitigating proteinuria in indications where there are no approved therapies

PATENT

WO 2000001389
https://www.google.co.in/patents/WO2000001389A1?cl=en



Example 41
4'- [(2-Butyl-4-oxo- 1.3-diazaspiro [4.4! non- l-en-3-yl)methyll -N-(3.4- dimethyl-5-isoxazolyl)-2'-hydroxymethyl[l, l'-biphenyl! -2-sulfonamide

A. 4'-[(2-Butyl-4-oxo-1.3-diazaspiro[4.41non-l-en-3-yl)methyll-N-(3.4- dimethyl-5-isoxazolyl)-N-[(2-trimethylsilylethoxy)methyl]-2'- hydroxym ethyl [1, l'-biphenyl] -2-sulfonamide P14 (243 mg, 0.41 mmol) was used to alkylate 2-butyl-4-oxo-l,3- diazaspiro[4.4]non-l-ene hydrochloride according to General Method 4. 41A (100 mg, 35% yield) was isolated as a slightly yellow oil after silica gel chromatography using 1:1 hexanes/ethyl acetate as eluant. B. 4'- [(2-Butyl-4-oxo- 1 ,3-diazaspiro [4.41 non- l-en-3-yl)methvn -N-0.4- dimethyl-5-isoxazolyl)-2'-hydroxymethyl[l,l'-biphenyn-2- sulfonamide
Deprotection of 41A (100 mg, 0.14 mmol) according to General Method 8 (ethanol) gave the title compound as white solid in 46% yield following silica gel chromatography (96:4 methanol/chloroform eluant):
MS m/e 565 (ESI+ mode); HPLC retention time 3.21 min (Method A);
HPLC purity >98%.
Example 42
4'-[(2-Butyl-4-oxo-1.3-diazaspiro[4.41non-l-en-3-yl)methvn-N-(3,4- dimethyl-5-isoxazolyl)-2'-ethoxymethyl [ 1 , l'-biphenyll -2-sulfonamide

A. 4'- [(2-Butyl-4-oxo- 1 ,3-diazaspiro [4.41 non- l-en-3-yl)methyll -N-(3 ,4- dimethyl-5-isoxazolyl)-N-[(2-methoxyethoxy)methyll-2'- hvdroxym ethyl [1 , l'-biphenyl] -2-sulfonamide
Triethylsilane (6 ml) and TFA (6 ml) were added to a solution of 5F (960 mg, 1.5 mmol) in 15 ml dichloromethane at RT. The mixture was stirred at RT for 2 h and was then concentrated. The residue was taken up in ethyl acetate and was washed successively with aqueous sodium bicarbonate, water, and brine. The organic layer was dried over sodium sulfate and concentrated. The residue was chromatographed on silica gel using 100:2 dichloromethane/methanol to afford 42A (740 mg, 77%) as a colorless gum. Rf=0.13, silica gel, 100:5 dichloromethane/methanol. B. 4'- [(2-Butyl-4-oxo- 1.3-diazaspiro [4.41 non- l-en-3-yl)methyll -N-(3.4- dimethyl-5-isoxazolyl)-N-r(2-methoxyethoxy)methyll-2'- ethoxymethyl[l.l'-biphenyll-2-sulfonamide A mixture of 42A (100 mg, 0.15 mmol), iodoethane (960 mg, 6.1 mmol) and silver (I) oxide (180 mg, 0.77 mmol) in 0.7 ml DMF was heated at 40 ° C for 16 h.. Additional iodoethane (190 mg, 1.2 mmol) and silver (I) oxide (71 mg, 0.31 mmol) were added and the reaction mixture was heated at 40 ° C for an additional 4 h. The mixture was diluted with 1:4 hexanes/ethylacetate and was then washed with water and brine. The organic layer was dried over sodium sulfate and was then concentrated. The residue was chromatographed on silica gel using 200:3 dichloromethane/methanol as eluant to afford 42B (51mg, 49%) as a colorless gum. Rf=0.35, silica gel, 100:5 dichloromethane/methanol.
C. 4^,-[(2-Butyl-4-oxo-1.3-diazaspirof4.41non-l-en-3-yl)methyll-N-(3.4- dimethyl-5-isoxazolyl )-2'-ethoxym ethyl [ 1. l'-biphenyll -2-sulfonamide
42B (51 mg) was deprotected according to General Method 7 to afford the title compound in 80% yield following preparative reverse-phase HPLC purification: white solid; m.p. 74-80 ° C (amorphous); IH NMR (CDCL, )δ0.87(tr, J=7Hz, 3H), 0.99(tr, J=7Hz, 3H), 1.32(m, 2H), 1.59(m, 2H), 1.75-2.02(m, 11H), 2.16(s, 3H), 2.35(m, 2H), 3.38 (m, 2H), 4.23(m, 2H), 4.73(s, 2H), 7.11-7.85 (m, 7H); MS m/e 593 (ESI+ mode); HPLC retention time 18.22 min. (Method E); HPLC purity >97%.

PATENT

WO 2001044239
http://www.google.co.in/patents/WO2001044239A2?cl=en
........................
Dual angiotensin II and endothelin A receptor antagonists: Synthesis of 2'-substituted N-3-isoxazolyl biphenylsulfonamides with improved potency and pharmacokinetics
J Med Chem 2005, 48(1): 171

J. Med. Chem., 2002, 45 (18), pp 3829–3835

DOI: 10.1021/jm020138n

http://pubs.acs.org/doi/abs/10.1021/jm020138n

 BMS 248360 A DIFFERENT COMPD

The ET_A receptor antagonist (2) (N-(3,4-dimethyl-5-isoxazolyl)-4‘-(2-oxazolyl)-[1,1‘-biphenyl]-2-sulfonamide, BMS-193884) shares the same biphenyl core as a large number of AT₁ receptor antagonists, including irbesartan (3). Thus, it was hypothesized that merging the structural elements of 2 with those of the biphenyl AT₁ antagonists (e.g., irbesartan) would yield a compound with dual activity for both receptors. This strategy led to the design, synthesis, and discovery of (15) (4‘-[(2-butyl-4-oxo-1,3-diazaspiro[4.4]non-1-en-3-yl)methyl]-N-(3,4-dimethyl-5-isoxazolyl)-2‘-[(3,3-dimethyl-2-oxo-1-pyrrolidinyl)methyl]-[1,1‘-biphenyl]-2-sulfonamide, BMS-248360) as a potent and orally active dual antagonist of both AT₁ and ET_Areceptors. Compound 15 represents a new approach to treating hypertension.

Scheme 2 ^{a  DIFFERENT COMPD}

^a (a) DIBAL, toluene; (b) NaBH₄, MeOH; (c) (Ph)₃P, CBr₄, THF (51% from 9); (d) compound 7, NaH, DMF; (e) 1 N HCl; (f) compound 4, (Ph₃P)₄Pd, aqueous Na₂CO₃, EtOH/toluene; (g) 6 N aqueous HCl/EtOH (60% from 10); (h) 13, sodium triacetoxy borohydride, AcOH, (i) diisopropylcarbodiimide, CH₂Cl₂ (31% from 12).

..........
WO 2010135350
http://www.google.com/patents/WO2010135350A2?cl=en
Compound 1 :

Scheme IV

Scheme V

Formula IV 1
Scheme VII

Formula Vl

A solution of 2-(2,4-dimethylphenyl)benzenesulfonic acid (Compound 12) (0.5 g, 1.9 mmol) in 50 mL of anhydrous acetonitrile was prepared and transferred to a round-bottom flask. After flushing with nitrogen gas, N-bromosuccinimide (0.75 g, 4.2 mmol) was added followed by 50 mg (0.2 mmol) of benzoyl peroxide. The solution was heated at reflux for 3 hours. The solvent was removed in-vacuo and the resulting syrup purified by silica gel chromatography (1 :1 hexanes/EtOAc) to yield Compound 13 as a white solid. ¹H NMR (500 MHz, CD3CN) 8.12 (d, J = 7.5 Hz, IH), 7.92 (t, J = 7.5 Hz, IH), 7.78 (d, J= 7.5 Hz, IH), 7.74-7.71 (m, 2H), 7.68-7.65 (m, 2H), 5.12 (s, 2H), 4.70 (s, 2H). Example 4 2-(4-Bromomethyl-2-ethoxymethylphenyl)benzenesulfonic acid (Compound 14)

A solution of 20 mg (0.058 mmol) of (l-bromomethylbenzo[3,4- d])benzo[l,2-f]-2-oxa-l,l-dioxo-l-thiocycloheptane (Compound 13) in ethanol was stirred at elevated temperature until the starting material was consumed to give crude product (compound 14) that was used directly in the next step without isolation or purification.
Example 5
2-(4-((2-Butyl-4-oxo-l,3-diazaspiro[4.4]non-l-en-3-yl)methyl>2- ethoxymethylphenyl)benzenesulfonic acid (Compound 15)

To the above ethanol solution of crude 2-(4-bromomethyl-2- ethoxymethylphenyl)benzenesulfonic acid (Compound 14) described in Example 4 was added approximately 25 mL of anhydrous DMF. The ethanol was removed from the system under reduced pressure. Approximately 15 mg (0.065 mmol) of 2-butyl-l,3- diazaspiro[4.4]non-l-en-4-one (compound 7 in Scheme IV) was added followed by 300 μL of a IM solution of lithium bis-trimethylsilylamide in THF. The solution was allowed to stir at room temperature for 3 hours. The solvents were removed under reduced pressure and the remaining residue purified by preparative RP-HPLC employing a Cl 8 column and gradient elution (H₂O:MeCN) affording the title compound as a white solid; [M+H]+ calcd for C₂₇H₃₄N₂O₅S 499.21, found, 499.31 ; ¹H NMR (500 MHz, CD3CN) 8.04 (t, J= 5.5 Hz, IH), 7.44-7.10 (m, 2H), 7.28 (s, IH), 7.22 (d, J= 8.0 Hz, 2H), 7.08- 7.04 (m, 2H), 4.74 (br s, 2H), 4.32 (d, J= 13.0 Hz IH), 4.13 (d, J= 13.0 Hz IH), 3.40- 3.31 (m, 2H), 2.66 (t, J= 8 Hz, 2H), 2.18-2.13 (m, 5H), 1.96-1.90 (m, 2H obscured by solvent), 1.48 (m, 2H), 1.27 (s, J= 7 Hz, 2H), 1.16 (t, J= 7 Hz, 3H), 0.78 (t, J= 7.5 Hz, 3H).
Example 6
2-(4-((2-Butyl-4-oxo-l,3-diazaspiro[4.4]non-l-en-3-yl)methyl>2- ethoxymethylphenyl)benzenesulfonyl chloride (Compound 16)

To a solution of DMF (155 μL, 2 mmol, 2 equiv.) in dichloromethane (5 mL) at 0 ⁰C was added dropwise oxalyl chloride (175 μL, 2 mmol, 2 equiv.) followed by a dichloromethane (5 mL) solution of 2-(4-((2-butyl-4-oxo-l,3-diazaspiro[4.4]non-l- en-3-yl)methyl)-2-ethoxymethylphenyl)benzenesulfonic acid (Compound 15) (0.50 g, 1.0 mmol). The resulting mixture was stirred at 0 ⁰C for ~2 hours, diluted with additional dichloromethane (25 mL), washed with saturated sodium bicarbonate solution (10 mL), water (10 mL), and brine (10 mL), dried over sodium sulfate, and then concentrated to give crude sulfonyl chloride (compound 16) that was used without purification.
Example 7
N-(3,4-Dimethyl-5-isoxazolyl)-2-(4-(2-butyl-4-oxo-l,3-diazospiro[4.4]non-l-en- 3yl)methyl-2-ethoxymethylphenyl)phenylsulfonamide (Compound 1)

[0062] To a solution of 5-amino-3,4-dimethylisoxazole (60 mg, 0.54 mmol) in THF at -60 °C was added dropwise potassium tert-butoxide (1 mL of 1 M solution) followed by a solution of crude 2-(4-((2-butyl-4-oxo-l,3-diazaspiro[4.4]non-l-en-3- yl)methyl)-2-ethoxymethylphenyl)benzenesulfonyl chloride (Compound 16) (0.28 g, 0.54 mmol) in THF (4 mL). The resulting mixture was stirred at about -60 °C for 1 hour, allowed to warm to room temperature overnight, and then quenched with IN HCl solution to about pH 4. Standard workup of extraction with ethyl acetate, washing with water, drying, and concentration provided the final compounds as a white solid. ¹H NMR (400 MHz, CDCl₃) 8.03 (dd, J = 8.0 and 1.2, IH), 7.60 (td, J = 7.5 and 1.5, IH), 7.50 (td, J = 7.7 and 1.5, IH), 7.36 (s, IH), 7.28 (d, J= 2.1, 1 H), 7.25 (dd, J = 7.5 and 1.2, IH), 7.09 (dd, J= 7.9 and 1.6, IH), 6.61 (bs, IH), 4.77 (AB quartet, J= 15.5 and 8.1, 2H), 4.18 (AB quartet, J= 12.0 and 35, 2H), 3.45-3.32 (m, 2H), 2.39 (t, J= 7.5, 2H), 2.26 (s, 3H), 2.02- 1.84 (m, 8H), 1.82 (s, 3H), 1.63 (quint, J = 7.5, 2H), 1.37 (sextet, J = 7.3, 2H), 1.07 (t, J = 7.0, 3H), and 0.90 (t J= 7.3, 3H).

Example 8 l-Bromo-2-ethoxymethyl-4-hydroxymethylbenzene (Compound 17)

To a solution of ethyl 4-bromo-3-ethoxymethylbenzoate (9.4 g, 33 mmol) in toluene (56 mL) at about -10 ⁰C was added 51 g of a 20% diisobutylaluminum hydride solution in toluene (ca. 70 mmol). The reaction was stirred at the same temperature for about 30 minutes until the reduction was completed, and then quenched with icy 5% NaOH solution to keep the temperature below about 10 °C. Organic phase of the resulting mixture was separated and the aqueous phase was extracted with toluene. The combined organic phase was concentrated in vacuo to a final volume of ~60 mL toluene solution of l-bromo-2-ethoxymethyl-4-hydroxymethylbenzene (Compound 17) that was used in next step without purification.
Example 9 l-Bromo-2-ethoxymethyl-4-methanesulfonyloxymethylbenzene (Compound 18)

To a solution of 1 -bromo-2-ethoxymethyl-4-hydroxymethylbenzene (Compound 17) (8.4 g, 33 mmol) in toluene (60 mL) prepared in Example 8 at about -10 °C was added methanesulfonyl chloride (7.9 g, 68 mmol). The reaction was stirred at the same temperature for about 30 minutes until the reduction was completed, and then quenched with icy water to keep the temperature at about 0 °C. The organic layer was separated and washed again with icy water to provide a crude product solution of 1 - bromo-2-ethoxymethyl-4-methanesulfonyloxymethylbenzene (Compound 18) that was used without purification.
Example 10
1 -Bromo-4-((2-butyl-4-oxo- 1 ,3 -diazaspiro [4.4]non- 1 -en-3 -yl)methy l)-2- ethoxymethylbenzene bisoxalic acid salt (Compound 19)

To the crude solution of 1 -bromo-2-ethoxymethyl-4- methanesulfonyloxymethylbenzene (Compound 18) (1 1 g, 33 mmol) in toluene (80 mL) prepared in Example 9 was added a 75% solution of methyltributylammonium chloride in water (0.47 mL). The resulting mixture was added to a solution of 2-butyl-4-oxo-l,3- diazaspiro[4.4]non-l-ene (compound 7 in Scheme VI) (7.5 g, 32 mmol) in dichloromethane (33 mL) pretreated with a 10 M NaOH solution (23 mL). The reaction mixture was stirred at room temperature for 2 hours until compound 18 was not longer detectable by HPLC analysis and then was quenched with water (40 mL). After stirring about 10 minutes, the organic layer was separated and aqueous layer was extracted with toluene. The combined organic phase was washed with water and concentrated to a small volume. Filtration through a silica gel pad using ethyl acetate as solvent followed by concentration yielded 1 -bromo-4-((2-buty 1-4-oxo- 1 ,3 -diazaspiro [4.4]non- 1 -en-3 - yl)methyl)-2-ethoxymethylbenzene as a crude oil product.
The crude oil was dissolved in ethyl acetate (22 mL) and warmed to around 50 °C. Anhydrous oxalic acid (4.6 g) was added to the warm solution at once and the resulting mixture was stirred until a solution was obtained. The mixture was cooled gradually and the bisoxalic acid salt (compound 19) was crystallized. Filtration and drying provided pure product (compound 19) in 50-60% yield from ethyl 4-bromo-3- ethoxymethylbenzoate in 3 steps. ¹H NMR (400 MHz, CDCl₃) 12.32 (bs, 4H), 7.58 (d, J = 7.8, IH), 7.36 (s, IH), 7.12 (d, J= 7.8, IH), 4.90 (s, 2H), 4.56 (s, 2H), 3.68 (q, J= 7.5, 2H), 2.87-2.77 (m, 2H), 2.40-1.95 (m, 8H), 1.62-1.53 (m, 2H), 1.38-1.28 (m, 4H), and 1.82 (t, J= 7.5, 3H).
Example 11
N-(3,4-Dimethyl-5-isoxazolyl)-2-(4-(2-butyl-4-oxo-l,3-diazospiro[4.4]non-l-en- 3yl)methyl-2-ethoxymethylphenyl)phenylsulfonamide (Compound 1)

To a suspension of l-bromo-4-((2-butyl-4-oxo-l,3-diazaspiro[4.4]non- l-en-3-yl)methyl)-2-ethoxymethylbenzene bisoxalic acid salt (Compound 19) (5.0 g, 8.3 mmol) in toluene (20 niL) under nitrogen was added water (30 mL) and pH was adjusted to 8-9 by addition of a 2 M NaOH solution at room temperature. The organic phase was separated and mixed with 2-(N-(3,4-dimethyl-5-isoxazolyl)-N- methoxymethylamino)sulfonylphenylboronic acid pinacol ester (Scheme VII, Formula IX, where R⁸is methoxymethyl and M = boronic acid pinacol ester) (3.6 g, 8.5 mmol), bis(dibenzylideneacetone)palladium(0) (Pd(dba)₂) (0.12 g), and a standard phosphine ligand. After a 2 M sodium carbonate solution was added, the reaction mixture was warmed to 70 ⁰C and stirred until the reaction was complete by HPLC analysis. The reaction was cooled to room temperature and quenched with water, and then separated in phases. The organic phase was treated with activated carbon, filtered through a pad of silica gel, and was concentrated to afford a crude mixture.
The crude reaction mixture was dissolved in ethanol (40 mL) after palladium catalyst was removed and was treated with 6 M HCl solution (ca. 40 mL). The mixture was warmed to 75-80 °C and stirred for about 2 hours until the reaction was completed by HPLC analysis. After the mixture was cooled to room temperature, the pH of the mixture was adjusted to 8 by addition of 10 M NaOH solution. The mixture was stirred for 2 more hours and the pH was adjusted to 6 by adding 2 M HCl and the crystal seeds. Filtration of the crystalline solid followed by drying provided N-(3,4-dimethyl-5- isoxazolyl)-2-(4-(2-butyl-4-oxo-l,3-diazospiro[4.4]non-l-en-3yl)methyl-2- ethoxymethylphenyl)phenylsulfonamide (Compound 1) as a white solid.¹H NMR (400 MHz, CDCIa) 8.03 (dd, J= 8.0 and 1.2, IH), 7.60 (td, J = 7.5 and 1.5, IH), 7.50 (td, J = 7.7 and 1.5, IH), 7.36 (s, IH), 7.28 (d, J= 2.1, 1 H), 7.25 (dd, J = 7.5 and 1.2, IH), 7.09 (dd, J= 7.9 and 1.6, IH), 6.61 (bs, IH), 4.77 (AB quartet, J= 15.5 and 8.1, 2H), 4.18 (AB quartet, J= 12.0 and 35, 2H), 3.45-3.32 (m, 2H), 2.39 (t, J= 7.5, 2H), 2.26 (s, 3H), 2.02- 1.84 (m, 8H), 1.82 (s, 3H), 1.63 (quint, J= 7.5, 2H), 1.37 (sextet, J= 7.3, 2H), 1.07 (t, J = 7.0, 3H), and 0.90 (t J= 7.3, 3H).

US20040002493 *	Aug 20, 2001	Jan 1, 2004	Kousuke Tani	Benzoic acid derivatives and pharmaceutical agents comprising the same as active ingredient
US20070054806 *	Sep 6, 2006	Mar 8, 2007	Bayer Cropscience Gmbh	Novel sulfonamide-comprising solid formulations
US20070054807 *	Sep 8, 2006	Mar 8, 2007	Bayer Cropscience Gmbh	Storage-stable formulations of sulfonamides

.//////////////Sparsentan, PS433540, RE-021, Bristol-Myers Squibb, ORPHAN DRUG, Retrophin
O=S(C1=CC=CC=C1C2=CC=C(CN3C(CCCC)=NC4(CCCC4)C3=O)C=C2COCC)(NC5=NOC(C)=C5C)=O