[F-18](2S,4S)-4-(3-Fluoropropyl)glutamine

CAS 1196963-79-7

MF C8 H15 F N2 O3

Heptanoic acid, 2-​amino-​4-​(aminocarbonyl)​-​7-​(fluoro-​18F)​-​, (2S,​4S)​-

[18F](2S,4S)-4-FPGln	[18F](2S,4S)-4-(3-fluoropropyl)glutamine, 4

The early diagnosis of malignant tumors plays a very important role in the survival prognosis of cancer patients. In this non-invasive diagnosis, diagnostic imaging procedures are an important tool. In the last few years has mainly PET technology (P ositronen- E mission-Tomographie) proved to be particularly useful. The sensitivity and specificity of PET technology depends significantly on the used signal-emitting substance (tracer) and their distribution in the body from. In the search for suitable tracers one tries to take advantage of certain properties of tumors differ, the tumor tissue from healthy, surrounding tissue. The preferred commercially used isotope which finds application for PET, 18 F 18 F represents by its short half-life of less than 2 hours special requirements for the preparation of suitable tracer.Complex, long synthetic routes and purifications are with this isotope is not possible, because otherwise a significant portion of the radioactivity of the isotope has already decayed before the tracer can be used for diagnosis. It is therefore often not possible to established synthetic routes for non-radioactive fluorination to be applied to the synthesis of18 F-tracer. Furthermore, the high specific activity of 18 F (80 GBq / nmol) at very low substance amounts of [18 F] fluoride for the tracer synthesis, which in turn an extreme excess of precursor-related and the success of a non-radioactive fluorination based Radio synthetic strategy designed unpredictable

FDG ([18 F] F 2 luoro d esoxy lukose g) -PET is a widely accepted and popular tool in the diagnosis and other clinical tracking of tumor diseases. Malignant tumors compete with the host organism to glucose supply to the nutrient supply (Warburg O. About the metabolism of carcinoma cell Biochem;.. Kellof G. Progress and Promise of FDG PET Imaging for Cancer Patient Management and Oncologic Drug Development Clin Cancer Res 2005;.. 11 (8): 2785-2807) where tumor cells compared to surrounding cells of normal tissue usually an increased glucose metabolism. This is used when using fluorodeoxyglucose (FDG), a glucose derivative, which is amplified transported into the cells, but there included metabolically after phosphorylation as FDG-6-phosphate (“Warburg effect”). 18 F-labeled FDG is Therefore, an effective tracer for the detection of tumors in patients using PET technology. Imaging were looking for new PET tracers in recent years increasingly amino acids for 18 F PET used (eg (review): Eur J Nucl Med Mol Imaging 2002 May; 29 (5):.. 681-90). In this case, some of the 18F-labeled amino acids for the measurement of the speed rate of protein synthesis, the most useful derivatives but for the direct measurement of the cellular uptake in the tumor. Known 18 F-labeled amino acids are, for example, from tyrosine, phenylalanine, proline, aspartic and unnatural amino acids derived (eg J. Nucl Med 1991; 32:.. 1338-1346, J Nucl Med 1996; 37: 320-325, J Nucl Med 2001; 42: 752-754 J Nucl Med and 1999, 40: 331-338).. Glutamic acid and glutamine than 18 F-labeled derivatives not known, whereas non-radioactive fluorinated glutamine and glutamic acid derivatives are well known; Thus, for Example those which at γ-position (for Ex (review):Amino Acids (2003) April; 24 (3):… 245-61).. or at β-position (e.g. ExTetrahedron. Lett. .; 30; 14; 1989, 1799-1802, J. Org Chem .; 54; 2; 1989, 498-500,Tetrahedron: Asymmetry, 12, 9; 2001; 1303-1312) havefluorine..

Of glutamic acid having the chemical functionalities protecting groups in β and γ position or a leaving group, has already been reported in the past. So was informed of glutamate as mesylate or bromide in γ-position whose acid and amine functions were provided with ester or Z-protecting groups (J. Chem Soc Perkin Trans. 1;.. 1986, 1323-1328) or, for example, of γ-chloro-glutamic acid without protecting groups(Synthesis, (1973); 44-46). About similar derivatives, but where the leaving group is positioned in β-position has also been reported on several occasions. Z Ex. Chem. Pharm. Bull .; 17; 5; (1969); 879-885,J.Gen.Chem.USSR (Engl.Transl.); 38; (1968); 1645-1648, Tetrahedron Lett .; 27; 19; (1986); 2143-2144, Chem. Pharm. Bull .; EN; 17; 5; 1969;873-878, patent FR 1461184 , Patent JP 13142 .)

The current PET tracers, which are used for tumor diagnosis have some undisputed disadvantages: in FDG accumulates preferably in those cells with increased glucose metabolism on, but there are also other pathological and physiological conditions of increased glucose metabolism in the cells involved and tissues, eg, Ex. of infection or wound healing (summarized in J. Nucl. Med. Technol. (2005), 33, 145-155). It is still often difficult to decide whether a detected by FDG-PET lesion actually neoplastic origin or due to other physiological or pathological state of the tissue. Overall, the diagnostic activity by FDG-PET in oncology has a sensitivity of 84% and a specificity of 88% to(Gambhir et al., ” A tabulated summary of the FDG PET literature “J. Nucl. Med. 2001, 42, 1- 93S). Tumors in the brain can be represented very difficult in healthy brain tissue, for example, by the high accumulation of FDG.

The previously known 18 F-labeled amino acid derivatives are in some cases well suited to detect tumors in the brain ((review): Eur J Nucl Med Mol Imaging 2002 May; 29 (5):. 681-90), but they can in other tumors do not compete with the imaging properties of the “gold standard”[18 F] 2-FDG. The metabolic accumulation and retention of previously F-18 labeled amino acids in tumorous tissue is usually lower than for FDG. Moreover, the accessibility of isomerically pure F-18-labeled non-aromatic amino acids is chemically very demanding.

Similar to glucose increased metabolism in proliferating tumor cells has been described (Medina, J Nutr 1131: 2539S-2542S, 2001; Souba, Ann Surg 218:. 715-728, 1993) for glutamic acid and glutamine. The increased rate of protein and nucleic acid synthesis and energy production per se be accepted as reasons for increased Glutaminkonsum of tumor cells. The synthesis of the corresponding C-11 and C-14 labeled with the natural substrate thus identical compounds, has already been described in the literature (eg. Ex.Antoni, enzymes Catalyzed Synthesis of L- [4-C-11] Aspartate and L – [5-C-11] Glutamate J. Labelled Compd Radiopharm 44; (4) 2001: 287-294) and Buchanan, The biosynthesis of showdomycin: studies with stable isotopes and the determination of principal precursor J….. Chem. Soc. Chem. Commun .;EN; 22; 1984, 1515-1517). First indications with the C-11 labeled compound indicate no significant tumor accumulation.

Although the growth and proliferation of most tumors is fueled by glucose, some tumors are more likely to metabolize glutamine. In particular, tumor cells with the upregulated c-Myc gene are generally reprogrammed to utilize glutamine. We have developed new 3-fluoropropyl analogs of glutamine, namely [(18)F](2S,4R)- and [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 3 and 4, to be used as probes for studying glutamine metabolism in these tumor cells. Optically pure isomers labeled with (18)F and (19)F (2S,4S) and (2S,4R)-4-(3-fluoropropyl)glutamine were synthesized via different routes and isolated in high radiochemical purity (≥95%). Cell uptake studies of both isomers showed that they were taken up efficiently by 9L tumor cells with a steady increase over a time frame of 120 min. At 120 min, their uptake was approximately two times higher than that of l-[(3)H]glutamine ([(3)H]Gln). These in vitro cell uptake studies suggested that the new probes are potential tumor imaging agents. Yet, the lower chemical yield of the precursor for 3, as well as the low radiochemical yield for 3, limits the availability of [(18)F](2S,4R)-4-(3-fluoropropyl)glutamine, 3. We, therefore, focused on [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4. The in vitro cell uptake studies suggested that the new probe, [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, is most sensitive to the LAT transport system, followed by System N and ASC transporters. A dual-isotope experiment using l-[(3)H]glutamine and the new probe showed that the uptake of [(3)H]Gln into 9L cells was highly associated with macromolecules (>90%), whereas the [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, was not (<10%). This suggests a different mechanism of retention. In vivo PET imaging studies demonstrated tumor-specific uptake in rats bearing 9L xenographs with an excellent tumor to muscle ratio (maximum of ∼8 at 40 min). [(18)F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, may be useful for testing tumors that may metabolize glutamine related amino acids.

[18F](2S,4S)-4-(3-Fluoropropyl)glutamine as a Tumor Imaging Agent

http://pubs.acs.org/doi/full/10.1021/mp500236y

Zehui Wu†, Zhihao Zha†, Genxun Li†, Brian P. Lieberman†, Seok Rye Choi†, Karl Ploessl†, and Hank F. Kung*†‡

†Departments of Radiology and ‡Pharmacology, University of Pennsylvania, 3700 Market Street, Philadelphia, Pennsylvania 19104, United States

Mol. Pharmaceutics, 2014, 11 (11), pp 3852–3866

DOI: 10.1021/mp500236y

Publication Date (Web): August 05, 2014

Copyright © 2014 American Chemical Society

*Email: kunghf@sunmac.spect.upenn.edu. Phone: 215-662-3096. Fax: 215-349-5035.

ACS AuthorChoice – This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

This article is part of the Positron Emission Tomography: State of the Art special issue.

Abstract

Although the growth and proliferation of most tumors is fueled by glucose, some tumors are more likely to metabolize glutamine. In particular, tumor cells with the upregulated c-Myc gene are generally reprogrammed to utilize glutamine. We have developed new 3-fluoropropyl analogs of glutamine, namely [18F](2S,4R)- and [18F](2S,4S)-4-(3-fluoropropyl)glutamine, 3 and 4, to be used as probes for studying glutamine metabolism in these tumor cells. Optically pure isomers labeled with 18F and 19F (2S,4S) and (2S,4R)-4-(3-fluoropropyl)glutamine were synthesized via different routes and isolated in high radiochemical purity (≥95%). Cell uptake studies of both isomers showed that they were taken up efficiently by 9L tumor cells with a steady increase over a time frame of 120 min. At 120 min, their uptake was approximately two times higher than that of l-[3H]glutamine ([3H]Gln). These in vitro cell uptake studies suggested that the new probes are potential tumor imaging agents. Yet, the lower chemical yield of the precursor for 3, as well as the low radiochemical yield for 3, limits the availability of [18F](2S,4R)-4-(3-fluoropropyl)glutamine, 3. We, therefore, focused on [18F](2S,4S)-4-(3-fluoropropyl)glutamine, 4. The in vitro cell uptake studies suggested that the new probe, [18F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, is most sensitive to the LAT transport system, followed by System N and ASC transporters. A dual-isotope experiment using l-[3H]glutamine and the new probe showed that the uptake of [3H]Gln into 9L cells was highly associated with macromolecules (>90%), whereas the [18F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, was not (<10%). This suggests a different mechanism of retention. In vivo PET imaging studies demonstrated tumor-specific uptake in rats bearing 9L xenographs with an excellent tumor to muscle ratio (maximum of ∼8 at 40 min). [18F](2S,4S)-4-(3-fluoropropyl)glutamine, 4, may be useful for testing tumors that may metabolize glutamine related amino acids.

PATENT

US 20100290991

http://www.google.com/patents/US20100290991

PATENT

WO 2009141091

https://patentscope.wipo.int/search/ko/detail.jsf?docId=WO2009141091&recNum=70&maxRec=287&office=&prevFilter=%26fq%3DOF%3ACU&sortOption=Relevance&queryString=&tab=PCTDescription

PATENT

http://www.google.co.ug/patents/EP2123621A1?cl=en

REFERENCES

https://www.researchgate.net/publication/264538736_F-182S4S-4-3-Fluoropropylglutamine_as_a_Tumor_Imaging_Agent

Molecular Pharmaceutics (2014), 11(11), 3852-3866

EP1923382A1 *	18 Nov 2006	21 May 2008	Bayer Schering Pharma Aktiengesellschaft	[18F] labelled L-glutamic acid, [18F] labelled glutamine, their derivatives, their use and processes for their preparation
FR1461184A				Title not available
JPS58113142A				Title not available
WO2008052788A1*	30 Oct 2007	8 May 2008	Bayer Schering Pharma Aktiengesellschaft	[f-18]-labeled l-glutamic acid, [f-18]-labeled l-glutamine, derivatives thereof and use thereof and processes for their preparation

////////

Rovatirelin Hydrate

Rovatirelin Hydrate, S-0373, 

Rovatirelin, RN: 204386-76-5
UNII: 9DL0X410PY

(4S,5S)-5-methyl-N-((2S)-1-((2R)-2-methylpyrrolidin-1-yl)-1-oxo-3-((1,3-thiazol-4-yl)methyl)propan-2-yl)-2-oxo-1,3-oxazolidine-4-carboxamide

(4S,5S)-5-methyl-N-((S)-1-((R)-2-methylpyrrolidin-1-yl)-1-oxo-4-(thiazol-4-yl)butan-2-yl)-2-oxooxazolidine-4-carboxamide4-Oxazolidinecarboxamide, 5-methyl-N-[2-(2-methyl-1-pyrrolidinyl)-2-oxo-1-(4-thiazolylmethyl)ethyl]-2-oxo-, [4S-[4α[R*(S*)],5α]]-

Phase III

A thyrotropin-releasing hormone potentially for the treatment of spinocerebellar ataxia.

CAS No.204386-76-5(Rovatirelin)

879122-87-9(Rovatirelin Hydrate)

C17H24N4O4S
Exact Mass: 380.1518

Rovatirelin is a novel synthetic agent that mimics the actions of thyrotropin-releasing hormone (TRH). Rovatirelin binds to the human TRH receptor with higher affinity (Ki=702nM) than taltirelin (Ki=3877nM). Rovatirelin increased the spontaneous firing of action potentials in the acutely isolated noradrenergic neurons of rat locus coeruleus (LC). Rovatirelin increased locomotor activity. Rovatirelin may have an orally effective therapeutic potential in patients with SCD.

Rovatirelin ([1-[-[(4S,5S)-(5-methyl-2-oxo oxazolidin-4-yl) carbonyl]-3-(thiazol-4-yl)-l-alanyl]-(2R)-2-methylpyrrolidine) is a novel synthetic agent that mimics the actions of thyrotropin-releasing hormone (TRH). The aim of this study was to investigate the electrophysiological and pharmacological effects of rovatirelin on the central noradrenergic system and to compare the results with those of another TRH mimetic agent, taltirelin, which is approved for the treatment of spinocerebellar degeneration (SCD) in Japan. Rovatirelin binds to the human TRH receptor with higher affinity (Ki=702nM) than taltirelin (Ki=3877nM). Rovatirelin increased the spontaneous firing of action potentials in the acutely isolated noradrenergic neurons of rat locus coeruleus (LC). The facilitatory action of rovatirelin on the firing rate in the LC neurons was inhibited by the TRH receptor antagonist, chlordiazepoxide. Reduction of the extracellular pH increased the spontaneous firing of LC neurons and rovatirelin failed to increase the firing frequency further, indicating an involvement of acid-sensitive K+ channels in the rovatirelin action. In in vivo studies, oral administration of rovatirelin increased both c-Fos expression in the LC and extracellular levels of noradrenaline (NA) in the medial prefrontal cortex (mPFC) of rats. Furthermore, rovatirelin increased locomotor activity. The increase in NA level and locomotor activity by rovatirelin was more potent and longer acting than those by taltirelin. These results indicate that rovatirelin exerts a central nervous system (CNS)-mediated action through the central noradrenergic system, which is more potent than taltirelin. Thus, rovatirelin may have an orally effective therapeutic potential in patients with SCD.

PATENT

WO 9808867

PATENT

WO 9945000 

PATENT

WO 2002017954

Example

Preparation of the compound represented by Example 1 set (IX)

The second step

Two

(First step)

Method described in the literature (Synth. Commun., 20, 3507 (1990)) synthesized N- in (tert- butoxide deer Lupo sulfonyl) one 3- (4 one-thiazolyl) one L Aranin (1, 21.79 g, 80 mmol) in Torifuruoro and the mixture was stirred acetic acid (80 ml) were added under ice-cooling for 2 hours and a half. Then stirred for 30 minutes at room temperature was added to the reaction mixture p- toluenesulfonic acid hydrate (15.22 g, 80 mmol). The reaction mixture was concentrated to dryness under reduced pressure. To remove excess Torifuruoro acetic acid by the obtained residue concentrated to dryness under reduced pressure by addition of water and methanol.Obtained obtained residue was collected by filtration crystals ether was added to precipitate the compound (2) 29.8 g (quantitative).

NMR (CD 3 OD): 9.01 (1H, d-, J = 1.8 Hz), 7.70 (2H ; yd), 7.46 (lH, d-, J = 1.8 Hz), 7.23 (2H, yd), 4.38 (1H, dd , J = 4.8 from and 3.8 from Hz), 3.45 (2H ; yd), 2.37 (3H, s).

(Second step)

I 匕合 product (2) 38.85 g E evening Nord (200 ml) of (112.8 mmol) – in THF (600 ml) solution, diphenyl di § zone methane while 攪袢 at room temperature (39 g, 201 mmol) in small portions over 30 minutes were added. The reaction mixture was stirred for 1 hour at room temperature, Ziv E sulfonyl di § zone methane (10 g, 51.5 mmol) was added and stirred for one hour. To the reaction mixture

After decomposing the excess reagent by the addition of acetic acid (0.1 ml), it was concentrated to dryness under reduced pressure and distilled off the solvent. The resulting residue (92 g) with ether (1 L) was crystallized to give compound (3) 49.05 g (96.1%).

mp: 139-140 ° C

[A] D = -34.7 ° (C = 1.006, CHC1 3) 23 ° C)

^ Cm IRCKB ” 1 : 1753, 1602, 1512, 1496, 1260, 1224, 1171, 1124, 1036, 1012. NMR (CD 3 0D): 8.92 (1H, D, J = 2 Hz), 7.70 (2H ; M ), 7.2-7.4 (13H, m) , 6.91 (1H, s), 4.62 (1H, t, J = 5.8 Hz), 3.47 (2H, d, J = 5.8 Hz), 2.36 (3H, s).

Elemental analysis (C 2E H 2S N 2 0 5 S 2 )

Calculated: C, 61.16; H, 5.13; N, 5.49; S, 12.56.

Measured value: C, 61.14; H, 5.32; N, 5.41; S, 12.46.

(Third step)

Cis-one L one 5-methyl-2-one O Kiso O Kisa ethylbenzthiazoline one 4-carboxylic acid 13.95 g (96.14 mmol), compound (3) 49.09 g (96.14 mmol ), N-hydroxybenzotriazole To Riazoru 2.6 g (19.23 mmol) and under ice-cooling in THF (1L) solution of Toryechiruamin 14.1 ml (lOlmmol), was added to the DCC (20.83g, 101 mmol). The cooling bath was removed after stirring for 10 minutes at the same temperature, and stirred for an additional 2 0 hours at room temperature. After removing the precipitated precipitate and the filtrate concentrated to dryness under reduced pressure an oily residue (82.7 g was obtained). The residue was filtered off and dissolved by heating to insoluble matter in acetic acid Echiru (700 ml). The filtrate was successively washed with sodium carbonate aqueous solution and water.After the addition of methanol (20 ml) the organic layer was dried with sulfuric acid mug Neshiumu, was concentrated to a small volume under reduced pressure.Precipitated collected by filtration and acetic acid E Ji Le crystals – ether (2: 3) washing to compound with a mixture (4) 35.69 g (79.8% ) was obtained. After addition was concentrated to dryness under reduced pressure of the mother liquor, and crystallized from acetic acid E Chiru ether mixture compound (4) 2.62 g (5.9% ) was obtained.

mp: 176-177 ° C

[A] D = -39.2 ° (C = 1.007, CHC1 3 , 24 ° C)

^ Cm IRiKB 1 : 1739, 1681, 1508, 1453, 1386, 1237, 1193, 1089.

NMR (CDC1 3 ): 8.71 (1H, d-, J = 1.8 Hz), 8.18 (lH, d-‘J = 3.9 from Hz), 7.2-7.4 (10H ; yd), 6.82 (1H, s), 6.66 (1H, d-, J = 1.8 Hz), 5.79 (1H, s), 5.12 (1H, yd), 4.94 (lH, yd), 4.35 (1H ; dd, J = 1.8 and 4.5 from Hz), 3.40 (1H ; dd, J 5.7 and 15 = Hz), 3.29 (1H ; dd, J = 4.5 of and 15 Hz), 1.27 (3H, d-, J = 6.3 Hz).

Elemental analysis (C 24 H 23 N 3 0 5 S)

Calculated: C, 61.92; H, 4.98; N, 9.03; S, 6.89.

Measured value: C ! 61.95; H, 5.01; N, 8.94; S ) 6.62.

(Fourth step)

Compound (4) 41.24 under ice-cooling to g (88.59 mmol), and the mixture was stirred Anisoru (240ml) and To Rifuruoro acetic acid (120 ml) and the mixture for 15 minutes. And the mixture was stirred for 2 hours 3 0 minutes further room temperature after removal of the cooling bath. The reaction mixture was added to the E one ether (500 ml) to the oily residue obtained by concentrated to dryness under reduced pressure was collected by filtration and pulverized. The resulting powder is water (50 ml) – was removed by filtration methanol (300 ml) warming dissolved insoluble matter in a mixture. The filtrate was concentrated to small volume under reduced pressure, and allowed to stand at room temperature for 3 days adding a seed crystal and methanol. The precipitated crystals were obtained Shi preparative filtration compound (5) 14.89 g (56.1%). The mother liquor was concentrated to dryness under reduced pressure, to give again further compound was crystallized from methanol one ether mixture of the (5) 10.3 g (38%). mp: 214-215 ° C

[]. -4.2 ° = (C = 0.5, H 2 0, 22 ° C)

^ Cm IRCKB 1 : 1753, 1707, 1655, 1548, 1529, 1409, 1343, 1264, 1236, 1102, 1092. NMR (DMS0-D6): 9.02 (1H, D, J = 1.8 Hz), 8.46 (1H, d-; J = 3.9 from Hz), 7.74 (1H, s),

7.38 (1H, d, J = 1.8 Hz), 4.77 (1H, dq, J = 6.6 and 8.7 Hz), 4.66 (1H, m), 4.21 (1H, d,

J = 8.7 Hz), 3.24 (IH, dd, J = 5.1 and 15 Hz), 3.13 (1H, dd, J = 8.4 and 15 Hz),

1.13 (3H, d, J = 6.6 Hz).

Elemental analysis (C U H 13 N 3 0 5 S)

Calculated: C ; 44.14; H, 4.38; N, 14.04; S ) 10.71.

Measured value: C, 43.94; H, 4.478; N, 14.09; S, 10.58.

(Fifth step)

Compound (5) 12.1 g, (40.48 mmol) and N- hydroxysuccinimide (4.66 g, 40,48 mM) under ice-cooling to THF (242 ml) suspension of,: DCC (8.35 g, 40.48 mmol) was added to 3 and the mixture was stirred for 10 minutes. The cooling bath was removed, and the mixture was further stirred at room temperature for 2 hours. The resulting compound N- hydroxysuccinimide ester solution of (5) was synthesized in a way described in the literature (Tetrahedron, 27, 2599 (1971 )) (R) – (+) – 2- Mechirupiro lysine hydrochloride (5.42 g) and Toryechiruamin (8.46 ml, was added at room temperature to THF (121 ml) suspension of 60.72 mmol). The reaction mixture was stirred for an additional 1 5 hrs. The filtrate after removal of the insoluble matter that has issued analysis was concentrated to dryness under reduced pressure. Residue (24.6 Ga) the insoluble material was removed by filtration was dissolved in water (150 ml). The filtrate was purified by gel filtration column chromatography one (MCI Gel CHP-20P, 600 ml). 4 0% aqueous methanol solution compound of the collected crude eluted cut off fractionated (IX) was obtained 8.87 g. Then after purification by silica gel column chromatography (black port Holm one methanol mixture), to give the compound was freeze-dried (IX) 5.37 g (35.7% ).

mp: 192-194 ° C

[A] D = -1.9 ° (C = 1.005, H 2 0, 25 ° C)

KB Cm- IR 1 : 1755, 1675, 1625, 1541, 1516, 1448, 1232, 1097.

NMR (CD 3 0D): 8.97 (1H, t, J = 2.1 Hz), 7.34 (1H, t, J = 2.1 Hz), 5.19 and 5.04 (total the IH, the each t, J = 7.5 Hz), 4.92 (1H , Dq, J = 6.6 And 8.7 Hz), 4.36 And 4.35 (1H, D, J = 8.7 Hz), 4.07 And 3.92 (Total IH, Eac M), 3.78 (1H ; M), 3.42 (1¾ M), 3.22 (2H, m), 1.5-2.0 ( 4H, m), 1.28 and 1.22 (total 3H, each d, J = 6.6 Hz), 1.21 and 1.02 (total 3H, each d, J = 6.6 Hz).

Elemental analysis (C 16 H 22 N 4 0 4 S H 2 0)

Calculated: C, 49.99; H, 6.29; N, 14.57; S, 8.34.

Measured value: C, 49.99; H, 6.29; N, 14.79; S, 8.36.

PATENT

WO 2006028277

Example

Example 1

B

Step 1 l-N-[N<tert-butoxycarbonyl)-3-(^^^

N.N-dicyclohexylcarbodiimide (10.83 g, 52.5 mmol), N-hydroxybenzotriazole (2.03 g, 15 mmol) and triethylamine (7.7 ml, 55.2 mmol) were added to a solution (130 ml) of N-(tert-butoxycarbonyl)-3-(thiazol-4-yl)-L-alanine (1) (13.62 g, 50 mmol) obtained by the method described in literatures (J. Am. Chem. Soc. 73, 2935 (1951) and Chem. Pharm. Bull. 38, 103 (1950)) and 2(R)-2-methylpyrrolidine p-toluenesulfonic acid (2) (12.79 g, 50 mmol) obtained by the method described in a literature (HeIv. Chim. Acta, 34, 2202 (1951)) in tetrahydrofuran. The mixture was stirred for 20 hours at room temperature. After the precipitates are filtered off, the obtained filtrate was concentrated under reduced pressure. Thus-obtained residue was dissolved in ethyl acetate (200 ml) and the solution were washed with an aqueous solution of sodium hydrogencarbonate and water, successively. The organic layers were dried over magnesium sulfate and concentrated under reduced pressure to give a title compound (3) (16.45 g, 100%) as oil.

NMR (CDCl3): OH 8.76 and 8.75 (1 H, each d, J=2.1Hz, Thia-H-2), 7.08 (1 H, d, J=2.fflz, thia-H-5), 5.45 (1 H, m, NH), 3.45-3.64 (1 H, m, AIa-CoH), 4.14 and 3.81 (1 H, each m, Pyr-CαH), 3.51 (1 H, m, PVr-NCH2), 3.1-3.4 (3 H, m, Pyr-CH2and AIa-CH2), 1.39 (9 H, s, BOC), 1.3-2.0 (4 H, m, PyT-CH2), 1.06 (3 H, d, J=6Hz, Pyr-Me)

Step 2 l-N-[3-(thiazol-4-yl)-L-alanyl]-(2R)-2-methylpyrroHdine di-p-toluenesulfcnate (4)

Compound (3) (33.77 g, 99.48 mmol) and p-toluenesulfonic acid hydrate (37.85 g, 199 mmol) were dissolved in ethyl acetate (101 ml) and the solution was cooled with ice. To the mixture, 4 mol/L solution of hydrogen chloride-ethyl acetate (125 ml) was added, and the mixture was stirred for 2 hours 45 minutes. After the mixture was concentrated under reduced pressure, methanol was added to the residue. The mixture was concentrated. Methanol-toluene (1: 1) was added to the residue and concentrated under reduced pressure to give crystalline residue. The residue was washed with acetone and filtered to give compound (4) as crystals (36 g, 62%). After the mother liquor was concentrated under reduced pressure, methanol and toluene were added to the residue and concentrated. Obtained crystalline residue was washed with acetone to give compound (4) (10.67 g, 18.4%). mp 188-189 0C [α]D 24 +2.2 (c, 1.0, MeOH) IR(KBr)Cm“1: 3431, 3125, 3080, 2963, 1667, 1598, 1537, 1497, 1451, 1364, 1229, 1198, 1170, 1123, 1035, 1011.

NMR (CD3OD): δH 9.04 and 9.03 (1 H, each d, J=2.1Hz, Thia-H-2), 7.70 (2 H, m, aromaticH), 7.46 (1H, d, J=2.1Hz, thia-H-5), 7.23 (2H, m, aromaticH), 4.49and4.46 (1 H, each d, J=6.9Hz, Ala-CαH), 4.14 and 3.75 (1 H, each m, Pyr-CαH), 3.51 (1 H, m, pyr-NCH2), 3.2-3.4 (3 H, m, PyT-CH2 and AIa-CH2), 2.36 (3 H, s, aromatic Me), 1.3-2.0 (4 H, m, pyr-CH2), 1.19 and 1.07 (3 H, each d, J=6.3Hz, Pyr-Me) Anal Calcd For C11H17N3OS 2C7H8O3S Calculated: C, 51.44%; H1 5.70%; N, 7.20%; S, 16.48%. Found: C, 51.36%; H, 5.69%; N, 7.23%; S, 16.31%.

Step 3 l-[N-[(4S,5S)-(5-methyl-2-oxooxazolidin-4-yl)carbonyl]-3-(thiazol-4-yl)-L-alanyl-(2R)-2- methylpyrrolidine trihydrate (I- 1) Step 3 (1) Method A

(4S, 5S)-5-methyl-2-oxooxazolidin-4-yl carboxylic acid (5) (1.368 g, 9.43 mmol) obtained by the method described in literatures (J. Chem. Soc. 1950, 62; Tetrahedron 48; 2507 (1992) and Angew. Chem. 101, 1392 (1989)), Compound (4) (5 g, 8.56 mmol) and N-hydiOxysuccinimide (217 mg, 1.89 mmol) were dissolved in N, N-dimethylformamide (10 ml), and tetrahydrofuran (65 ml) was added. After the mixture was cooled with ice in a cool bath, triethylamine (2.63 ml, 18.86 mmol) and N, N-dicyclohexylcarbodiimide (2.04 g, 9.89 mmol) were added with stirred and the mixture was stirred for additional 30 minutes. The cooling bath was removed and the mixture was stirred for 15 hours at room temperature. The precipitated were filtered off and the filtrate was concentrated under reduced pressure. Water (100 ml) was added to thus-obtained residue (9.95 g) and the mixture was stirred for 1.5 hours at room temperature. After insoluble substance was filtered off, the filtrate was concentrated until it was reduced to about half volume under reduced pressure. The small amount of insoluble substance was filtered off and the filtrate was concentrated until it was reduced to about 2O g under reduced pressure. After the mixture was allowed to stand in a refrigerator for 3 days, the precipitated crystals (2.98 g) were collected by filtration and washed with cold water. The filtrate was extracted twice with chloroform, dried over magnesium sulfate and concentrated under reduced pressure. Ethyl acetate (5 ml) was added to oil residue (1.05 g) and the mixture was stirred to give crystals (136 mg). The obtained crystals were combined and dissolved in purified water (45 ml) with heating. After the solution was allowed to cool to room temperature, the precipitated insoluble substance was filtered off The filtrate was concentrated under reduced pressure and allowed to stand at room temperature overnight. The mixture was cooled with ice, and the crystals were collected by filtration to give Compound (1-1, 2.89 g, 80.3%). mp 194-196 0C

[α]D 22 -2.0 ± 0.4 ° (c, 1.008, H2O), [α]365 +33.1 ± 0.7 ° (c, 1.008, H2O)

IR(Nujor)cm”1: 3517, 3342, 3276, 3130, 3092, 3060, 1754, 1682, 1610, 1551, 1465, 1442,

1379, 1235, 1089. NMR(CD3OD): δH 8.97 and 8.96 (total 1 H, d, J=2.1Hz, Thia-H-2), 7.34 and 7.33 (total 1

H, d, J=2.1Hz, Thia-H-5), 5.18 and 5.04 (total 1 H, each t, J=7.5Hz, Ala-CαH), 4.92 (1

H, dq, J=6.6 and 8.7Hz, Oxa-H-5), 4.36 and 4.35 (total 1 H, d, J=8.7Hz, Oxa-H-4), 4.07 and 3.92 (total 1 H, each m, Pyr-Cα-H), 3.78 (1 H, m, Pyr-NCH2), 3.42 (1 H, m, Pyr- 5 NCH2), 3.22 (2 H, m, AIa-CH2), 1.5-2.0 (4 H, m, Pyr-CH2), 1.28 and 1.22 (total 3 H, each d, J=6.6Hz, Oxa-5-Me), 1.21 and 1.02 (total 3 H, each d, J=6.6Hz, Pyr-2-Me)

Anal. Calcd For C16H22N4O4S 3H2O

Calculated: C, 45.00%; H, 6.71%; N, 13.33%; S, 7.63%.

Found: C, 45.49%; H, 6.60%; N, 13.58%, S, 7.88%. 10

Step 3 (2)

Method B

After Compound (1-2) (410 g, 1.119 mmol) was dissolved in purified water (6.3 L) with heating, the solution was concentrated until the total weight of the mixture was 15 reduced to 1370 g under reduced pressure. The concentrated solution was allowed to stand at room temperature overnight. The solution was cooled with ice for 1 hour and filtered to give the precipitated crystals. The obtained crystals were washed with cold water to give

Compound (T- 1) (448 g, 95.2%) as colorless crystals. Mother liquor was mixed with purified water (300 mL) with heating and the solution was concentrated to 55 g under reduced pressure. 20 After the concentrated solution was allowed to stand at room temperature overnight, the solution was filtered to give the precipitated crystals (T-1, 16.3 g, 3.5%, total amount 464.3 g, 98.7%). mp 194-196 0C

[α]D 22 -0.9 ± 0.4 ° (c, 1.007, H2O), [α]365 + 35.4 ± 0.8 ° (c, 1.007, H2O)

IR(NuJOr)Cm“1: 3511, 3348, 3276, 3130, 3093, 3060, 1755, 1739, 1682, 1611, 1551, 1465, 25. 1442, 1379, 1235, 1089.

AnalCalcdFor: C16H22N4O4S 3H2O

Calculated: C, 45.00%;H, 6.71%;N, 13.33%; S, 7.63%.

Found: C, 45.56%; H, 6.66%; N, 13.43%, S, 7.69%.

30 Step 4 l-[N-[(4S)5S)-(5-methyl-2-oxooxazolidin-4-yl)carbonyl]-3-(thiazol-4-yl)-L-alanyl-(2R)-2- methylpyrrolidine (1-2)

Method A

After l-[N-[(4S,5S)-(5-methyl-2-oxooxazolidin-4-yl)carbonyl]-3-(thiazol-4-yl)-L- 35 alanyl-(2R)-2-methylpyrrolidine monohydrate (4.77 g) obtained by the method described in Patent Literature 8 was crushed in a mortar, it was dried under reduced pressure (66.5 Pa) at 100 0C for 15 hours to give 4.54 g of Compound (1-2). mp 194.5-196.5 0C [α]D 25 -2.1 +. 0.4 ° (c, 1.004, H2O), [α]365 +36.8 ± 0.8 ° (c, 1.004, H2O) Water measurement (Karl Fischer method): 0.27%

IR(NuJOr)Cm”1: 3276, 3180, 3104, 1766, 1654, 1626, 1548, 1517, 1457, 1380, 1235, 1102, 979. NMR(CD3OD):δH 8.97 and 8.96 (total 1 H, d, J 2.1 Hz, Thia-H-2), 7.34 and 7.33 (total 1 H, d, J 2.1 Hz, Thia-H-5), 5.19 and 5.04 (total 1 H, each t, J 7.5 Hz, Ala- CaH), 4.92 (1 H, dq, J 6.6 and 8.7 Hz, Oxa-H-5), 4.36 and 4.35 (total 1 H, d, J 8.7 Hz, Oxa-H-4), 4.07 and 3.92 (total 1 H, each m, Pyr-Cα-H), 3.78 (1 H, m, Pyr-NCH2), 3.42 (1 H, m, Pyr-NCH2), 3.22 (2 H, m, AIa-CH2), 1.5-2.0 (4 H, m, Pyr-CH2), 1.28 and 1.22 (total 3 H, each d, J 6.6 Hz, Oxa-5-Me), 1.21 and 1.02 (total 3 H, each d, J 6.6 Hz, Pyr-2-Me). Anal Calcd For: C16H22N4O4S

Calculated: C, 52.44%; H, 6.05%; N, 15.29%; S, 8.75%. Found: C, 52.24%; H, 5.98%; N, 15.27%, S, 8.57%.

Method B

After Compound (1-1) (17.89 g, 47.3 mmol) was crushed in a mortar, it was dried under reduced pressure (66.5 Pa) at 100 °C for 14 hours to give Compound (1-2, 17.31 g). mp 193-194 0C [α]D 25 -1.9 ± 0.4 ° (c, 1.002, H2O), [α]365 +37.2 ± 0.8 ° (c, 1.002, H2O)

Water measurement (Karl Fischer method): 0.22%

IR(NuJOr)Cm“1: 3273, 3180, 3111, 1765, 1685, 1653, 1626, 1549, 1516, 1456, 1346, 1331,

1277, 1240, 1097, 980.

Anal Calcd For C16H22N4O4S Calculated: C, 52.44%; H, 6.05%; N, 15.29%; S, 8.75%.

Found: C, 52.19%; H, 5.98%; N, 15.42%, S, 8.74%.

REFERENCES

1: Ijiro T, Nakamura K, Ogata M, Inada H, Kiguchi S, Maruyama K, Nabekura J,
Kobayashi M, Ishibashi H. Effect of rovatirelin, a novel thyrotropin-releasing
hormone analog, on the central noradrenergic system. Eur J Pharmacol. 2015 Aug
15;761:413-22. doi: 10.1016/j.ejphar.2015.05.047. Epub 2015 Jul 2. PubMed PMID:
26142830.

////////Rovatirelin Hydrate, S-0373, Rovatirelin, 204386-76-5, clinical, phase 3

C[C@@H]1CCCN1C(=O)[C@H](Cc2cscn2)NC(=O)[C@@H]3[C@@H](OC(=O)N3)C

Flow synthesis of fluoxetine

Scheme 1: Flow synthesis of fluoxetine (46).

One of the early published examples of industry-based research on multi-step flow synthesis of a pharmaceutical was reported in 2011 by scientists from Eli Lilly/UK and detailed the synthesis of fluoxetine 46, the API of Prozac[1]. In this account each step was performed and optimised individually in flow, with analysis and purification being accomplished off-line. The synthesis commences with the reduction of the advanced intermediate ketone 47 using a solution of pre-chilled borane–THF complex (48) to yield alcohol 49 (Scheme 1).

Conversion of the pendant chloride into iodide 51 was attempted via Finckelstein conditions, however, even when utilising phase-transfer conditions in order to maintain a homogeneous flow regime the outcome was not satisfactory giving only low conversions. Alternatively direct amination of chloride 49 utilising high temperature flow conditions (140 °C) allowed the direct preparation of amine 50 in excellent yield.

Flow processing using a short residence time (10 min) at the elevated temperature allowed for a good throughput; in addition, the handling of the volatile methylamine within the confines of the flow reactor simplifies the practical aspects of the transformation, however, extra precautions were required in order to address and remove any leftover methylamine that would pose a significant hazard during scaling up.

 

The final arylation of 50 was intended to be performed as a S_NAr reaction, however, insufficient deprotonation of the alcohol 50 under flow conditions (NaHMDS or BEMP instead of using a suspension of NaH as used in batch) required a modification to the planned approach. To this end a Mitsunobu protocol based on the orchestrated mixing of four reagent streams (50, 54 and reagents 52 and 53) was developed and successfully applied to deliver fluoxetine (46) in high yield.

Overall, this study is a good example detailing the intricacies faced when translating an initial batch synthesis into a sequence of flow steps for which several adaptations regarding choice of reagents and reaction conditions are mandatory in order to succeed.

1. Ahmed-Omer, B.; Sanderson, A. J. Org. Biomol. Chem. 2011, 9, 3854–3862. doi:10.1039/C0OB00906G
   
   Paper

   Preparation of fluoxetine by multiple flow processing steps

   Batoul Ahmed-Omer^a and   Adam J. Sanderson*^a  

    

   *Corresponding authors

   ^aEli Lilly and Co. Ltd., Lilly Research Centre, Erl Wood Manor, Windlesham, Surrey, UK

   Org. Biomol. Chem., 2011,9, 3854-3862

   DOI: 10.1039/C0OB00906G
   http://pubs.rsc.org/en/Content/ArticleLanding/2011/OB/c0ob00906g#!divAbstract

Microflow technology is established as a modern and fashionable tool in synthetic organic chemistry, bringing great improvement and potential, on account of a series of advantages over flask methods. The study presented here focuses on the application of flow chemistry process in performing an efficient multiple step syntheses of (±)-fluoxetine as an alternative to conventional synthetic methods, and one of the few examples of total synthesis accomplished by flow technique.

1 The general method set-up of flow process used for the synthesis of (±)- fluoxetine.

Scheme 1 Synthesis of (±)-fluoxetine in flow: (i) BH3·THF, r.t., 5 min (77%); (ii) NaI, toluene: water, 100 °C, 20 min (43%); (iii); MeNH2 (aq), ...

//////////Flow synthesis, fluoxetine