Reference

Carboxyalkyl dipeptides

Carboxyalkyl dipeptides. Greenlee, William J. (Merck and Co. 13485-59-1 is the cas registry number. This chemical is also mentioned in this article., Inc. , USA). U.S. US 4442030 A 10 Apr 1984, 5 pp. Cont.-in-part of U.S. Ser. No. 385,745, abandoned. (English). (United States of America). CODEN: USXXAM. CLASS: IC: C07C103-52. NCL: 260112500R. APPLICATION: US 83-462727 31 Jan 1983. PRIORITY: US 82-385745 7 Jun 1982. DOCUMENT TYPE: Patent CA Section: 34 (Amino Acids, Peptides, and Proteins) Title compds. RCH2CH2CH(CO2R1)-X-X1-OH [R = (un)substituted aryl or heteroaryl; R1 = C1-4 alkyl; X = Ala, Gly, Ile, Leu, Lys, Phe, Val; X1 = Ala, Gly, Ile, Leu, Lys, Phe, Pro, Val] were prepd. from BzCH:CHCO2H (I) and the appropriate dipeptide. Thus, H-L-Ala-L-Pro-OH was treated with I in EtOH for 48 h and the mixt. was cooled and treated with EtOH/HCl and then hydrogenated over Pd/C to give a 1:1 mixt. of diastereomers of PhCH2CH2CH(CO2Et)-L-Ala-L-Pro-OEt. The latter mixt. was partially deblocked by HBr/HOAc and 48% aq. HBr and the resulting diastereomers were sepd. by maleic acid to give the maleate salt of (S)-PhCH2CH2CH(CO2Et)-L-Ala-L-Pro-OH. .