Reference

Optical resolution of DL-cysteine hydrochloride with D-(-)-mandelic acid

All Rights Reserved. Several substances are used for example 32443-99-5 and 10318-18-0 which are their cas registry numbers. Optical resolution of DL-cysteine hydrochloride with D-(-)-mandelic acid. Zhang, Tao; Xu, Bing-bing; Luo, Guang-hui; Feng, Lei; Hu, Wei; Shi, Xiao-hua; Chen, Xin-zhi (College of Material Science and Chemical Engineering, Zhejiang University, Hangzhou 310027, Peop. Rep. China). Jingxi Yu Zhuanyong Huaxuepin, 14(6), 26-28 (Chinese) 2006 Jingxi Yu Zhuanyong Huaxuepin Bianjibu. CODEN: JYZHA7. ISSN: 1008-1100. DOCUMENT TYPE: Journal CA Section: 34 (Amino Acids, Peptides, and Proteins) The resoln. of DL-cysteine hydrochloride to get D-cysteine hydrochloride using D-(-)-mandelic acid as the reagent has been reported. The diastereomer salt formed by reacting DL-cysteine hydrochloride with D-(-)-mandelic acid in the water and the salt was purified and then decompd. by aq. HCl. D-cysteine was obtained finally by recrystn. in 10% ethanol-acetone soln. with resoln. yield of 25.6%. .

Preparation of N-acylcystine derivatives as immunomodulating agents

Preparation of N-acylcystine derivatives as immunomodulating agents. Andersson, Carl Magnus Alexander; Bergstrand, Sten Haekan Axel; Hallberg, Anders Rudolf; Saernstrand, Bengt Olof; Tunek, Per Anders Sigvard (Astra AB, Swed.). Eur. Pat. Appl. EP 463514 A1 2 Jan 1992, 34 pp. DESIGNATED STATES: R: AT, BE, CH, DE, DK, ES, FR, GB, GR, IT, LI, LU, NL, SE. (European Patent Organization). CODEN: EPXXDW. CLASS: ICM: C07C323-59. ICS: A61K031-195; A61K031-22; A61K031-225. APPLICATION: EP 91-109808 14 Jun 1991. 32443-99-5 and 142-61-0 which are cas registry numbers are also used here. PRIORITY: SE 90-2274 28 Jun 1990; SE 90-2275 28 Jun 1990. DOCUMENT TYPE: Patent CA Section: 34 (Amino Acids, Peptides, and Proteins) The title compds. [I; R = H, COR1; R1 = (CH2)nMe, Me2CH, CHMeEt, CMe3, CH2CH2CHMe2, CH2CHMeCH2Me; n = 0-10; R2 = group listed R1; R3 = H, Me, Et, Pr, Me2CH, Bu, Me2CHCH2, R1 and R2 simultaneously 1 Me; when R3 = H, R1 and R2 simultaneously 1 Pr, n-heptyl] are prepd., e.g. by oxidn. of HSCH2CH(CO2R3)NHCOR1 (R1, R3 as defined above or optionally an alkali salt thereof when R3 = H) or acylation of a N-unprotected cystine ester R1COX which is an acid halide, anhydride, amide, or an activated acid ester. Thus, 4 equiv (Me2CH)2NEt and 2 equiv pentanoyl chloride were added to a stirred, cooled (0°) suspension of L-cystine di-Me ester-2HCl in THF and the mixt. was stirred for 4 h on an ice-bath to give (R,R)-I (R = COR2 = pentanoyl, R3 = Me). I at 3.0 mmol/kg increased 17-62% immunostimulating action in a model of delayed type hypersensitivity using mice sensitized with 4-ethoxymethylene-2-phenyloxazolone. .