Helvetica Chimica Acta p. 563 - 580 (1995)
Update date:2022-08-05
Topics:
Obrecht
Bohdal
Broger
Bur
Lehmann
Ruffieux
Schonholzer
Spiegler
Muller
This work describes L-phenylalanine cyclohexylamide (5c) as a simple, cheap, and powerful chiral auxiliary for the synthesis of a series of optically pure α,α-disubstituted (R)- and (S)-amino acids of type 1, such as (R)- and (S)-2-methyl-phenylalanine (1a), (R)- and (S)-2-methyl-2-phenylglycine (1b), and (R)- and (S)-2-methylvaline (1c). These amino acids were efficiently transformed into the suitably protected and activated amino-acid building blocks (R)- and (S)-12b and (R)- and (S)-12c which are ready for incorporation into peptides by solution or solid-phase techniques. Based on the crystal structures of 6b, 6c, and 7a belonging to the diastereoisomeric peptides series 6 and 7, the absolute configurations of each member of the series were determined. β-Turn geometries of type II' and I were observed for 6b and 7a, respectively, whereas 6c crystallized in an extended conformation. The impacts of side-chain variation on conformation and crystal packing of these triamides are discussed.
View MoreShanghai Sungo Technology Chemical Co., Ltd
Contact:0086-21-51385579
Address:Room2010, F/20, Tonghua Plaza, NO 345 Jinxiang Road, Jinqiao Export Processing Zone, Shanghai, 201206 P.R.CHINA
Zhejiang Haizhou Pharmaceutical Co., Ltd.
website:https://www.haizhoupharma.com/
Contact:+86 576 88221016
Address:No. 19, Donghai 5th Avenue, Yanhai Industrial Zone, Linhai, Zhejiang, China
Contact:18710867521(wechat)
Address:Rm10516,Galaxy Tech Building #2,No.25 Tangyan Rd,Hi-Tech Zone,Xi'an, China
website:http://www.hybio.com.cn
Contact:+86 755 26588093
Address:No.9 Linkong West Street, Hengdian Street, Huangpi District, Wuhan City, China.
SJZ Chenghui Chemical Co., Ltd.
Contact:86-311-87713916
Address:no.368 youyi north avenue
Doi:10.1039/c19650000574
(1965)Doi:10.1016/S0022-328X(00)93086-9
(1967)Doi:10.1248/cpb.47.1685
(1999)Doi:10.1177/1747519819866402
(2019)Doi:10.1016/0040-4039(95)01166-F
(1995)Doi:10.1080/10426500108546529
(2001)