19291-02-2Relevant articles and documents
Asymmetric Transformation of (RS)-Cysteine via Formation of (RS)-4-Thiazolidinecarboxylic Acids
Shiraiwa, Tadashi,Kataoka, Kazuo,Sakata, Shinji,Kurokawa, Hidemoto
, p. 109 - 113 (1989)
Either (R)- or (S)-cysteine ((R)- or (S)-Cys) was efficiently obtained from (RS)-Cys by the asymmetric transformation via formation of (RS)-thiazolidinecarboxylic acid ((RS)-THC) or (RS)-2,2-dimethyl-4-thiazolidinecarboxylic acid ((RS)-DMZ) and by using (2R,3R)- or (2S,3S)-tartaric acid ((R)- or (S)-TA), as a resolving agent, in acetic acid.The asymmetric transformation was carried out by combination of crystallization of less soluble salt of (S)-THC or -DMT with (R)-TA (or salt of (R)-THC or -DMT with (S)-TA) and epimerization of soluble diastereomeric salt.The (R)- and (S)-THCs from the less soluble salts gave approximately optically pure (R)- and (S)-Cys's, respectively, in 64percent yield.The asymmetric transformation via formation of (RS)-DMT was more succeefully achieved by adding 0.1 molar equivalent of salicylaldehyde; that is, hydrolysis of the obtained less soluble salt gave optically pure (R)- and (S)-Cys's, respectively, in 80percent yield based on the (RS)-Cys used as the starting material.
Asymmetric Transformation of DL-4-Thiazolidinecarboxylic Acid
Shiraiwa, Tadashi,Kataoka, Kazuo,Kurokawa, Hidemoto
, p. 2041 - 2042 (1987)
A mixture of DL-4-thiazolidinecarboxylic acid (DL-THC), (+)- or (-)-tartaric acid ((+)- or (-)-TA), and salicylaldehyde in acetic acid was stirred at 80 deg C to give a salt composed of equimolar amounts of L-THC and (-)-TA or that of D-THC and (+)-TA.D- and L-THC with optical purity of 97-99percent were obtained from these salts in 68-78percent yield.
Note on a new and simple synthesis of cystine from serine
Rambacher
, p. 2595 - 2597 (1968)
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PROCESS FOR PURIFYING (METH)ACRYLIC ACID
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Page/Page column 7-8, (2014/10/03)
A process for producing a grade of (meth)acrylic acid having residual formaldehyde levels of under 100 parts per million.
EFFICIENT SYNTHESIS OF CHELATORS FOR NUCLEAR IMAGING AND RADIOTHERAPY: COMPOSITIONS AND APPLICATIONS
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Page/Page column 95-96, (2008/06/13)
Novel methods of synthesis of chelator-targeting ligand conjugates, compositions comprising such conjugates, and therapeutic and diagnostic applications of such conjugates are disclosed. The compositions include chelator-targeting ligand conjugates optionally chelated to one or more metal ions. Methods of synthesizing these compositions in high purity are also presented. Also disclosed are methods of imaging, treating and diagnosing disease in a subject using these novel compositions, such as methods of imaging a tumor within a subject and methods of diagnosing myocardial ischemia.
NOVEL DIPEPTIDYL PEPTIDASE IV INHIBITORS, PHARMACEUTICAL COMPOSITIONS CONTAINING THEM, AND PROCESS FOR THEIR PREPARATION
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Page/Page column 45, (2008/06/13)
The present invention relates to novel compounds useful as dipeptidyl peptidase IV (DPP-IV) inhibitors of the formula: (I) wherein Y is -S(O)m, -CH2-, CHF, or -CF2; m is 0, 1, or 2; X is a bond, C1-C5 alkyl (e.g., -CH2-), or -C(=0)-; the dotted line [----] in the carbocyclic ring represents an optional double bond; R1 is substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted aryl, substituted or unsubstituted arylalkyl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heterocyclic ring, substituted or unsubstituted heterocyclylalkyl, substituted or unsubstituted heteroarylalkyl, CN, -COOR3, CONR3R4, -OR3, -NR3R4, or NR3COR3; R2 is hydrogen, cyano, COOH, or an isostere of a carboxylic acid (such as SO3H, CONOH, B(OH)2, PO3R3R4, SO2NR3R4, tetrazole, -COOR3, -CONR3R4, NR3COR4, or -COOCOR3).
