- Synthesis of Optically Active 1,4-Thiazane-3-carboxylic Acid via Optical Resolution by Preferential Crystallization of (RS)2-Amino-3-[(2-chloroethyl)sulfanyl]propanoic Acid Hydrochloride
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Optically active 1,4-thiazane-3-carboxylic acid [TCA] was synthesized from cysteine via optical resolution by preferential crystallization. The intermediate (RS)-2-amino-3-[(2-chloroethyl)sulfanyl]propanoic acid hydrochloride [(RS)-ACS-HCl] was found to exist as a conglomerate based on its melting point, solubility and IR spectrum. (RS)-ACS·HCl was optically resolved by preferential crystallization to yield (R)- and (S)-ACS·HCl. (R)- and (S)-ACS·HCl thus obtained were recrystallized from a mixture of hydrochloric acid and 2-propanol, taking account of the solubility of (RS)-ACS·HCl, efficiently yielding both enantiomers in optically pure forms. (R)- and (S)-TCA were then respectively synthesized by the cyclization of (R)- and (S)-ACS·HCI in ethanol in the presence of triethylamine.
- Shiraiwa, Tadashi,Tadokoro, Kohya,Tanaka, Haruyuki,Nanba, Keiichiro,Yokono, Noriyoshi,Shibazaki, Katsuyoshi,Kubo, Motoki,Kurokawa, Hidemoto
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- MACROCYCLIC FUSED PYRRAZOLES AS MCL-1 INHIBITORS
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Provided are compounds represented by Formula IA: (IA), and the pharmaceutically acceptable salts and solvates thereof, wherein R, R 1a, R 1b, L 1, L 2, L 3, X, A, B and C are as defined as set forth
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Paragraph 0913
(2020/08/13)
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- Thiazine amide derivative thereof in the preparation of medicaments for preventing neurodegenerative diseases, the use of the
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The invention relates to a compound shown as the formula I, pharmaceutically acceptable salts of the compound, and/ or solvates and/ or hydrates of the compound. The invention also relates to a preparation method of the compound, a medicinal composition c
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Paragraph 0021; 0028-0029
(2017/02/23)
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- Thiazine Amide Derivative and Pharmaceutical Composition and Use Thereof
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The present invention relates to a thiazine amide derivative and a pharmaceutical use thereof, and particularly to a compound of formula I (in the formula, variables are as described in the specification), a pharmaceutically acceptable salt, solvate or hy
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Paragraph 0062
(2015/07/27)
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- THIAZINE AMIDE DERIVATIVE AND PHARMACEUTICAL COMPOSITION AND USE THEREOF
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The present invention relates to a thiazine amide derivative and a pharmaceutical use thereof, and particularly to a compound of formula I (in the formula, variables are as described in the specification), a pharmaceutically acceptable salt, solvate or hy
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Paragraph 0043
(2015/07/15)
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- Substituted 6?membered n?heterocyclic compounds and their uses as neurological regulator
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This invention relates to substituted 6-membered N-Herterocyclic neurotrophic compounds of formula (I) or pharmaceutically acceptable salts or hydrates thereof, wherein R1, R2, X, Y, and Z are as defined in the description; their pre
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Page/Page column 6
(2008/06/13)
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