A rapid and efficient access to renieramycin-type alkaloids featuring a temperature-dependent stereoselective cyclization.
A flexible and practical protocol for the asymmetric synthesis of renieramycin-type antitumor alkaloids is described, in which the stereoselective Pictet-Spengler cyclization of amino ester 16 and aldehyde 15 by regulating temperature and the automatic lactamization after N-deprotection of the cyclization product are exploited to rapidly construct the common pentacyclic framework. (-)-Renieramycin G and (-)-jorunnamycin A, as representative members of the two subgroup renieramycin-type alkaloids, are obtained in 19 steps from l-tyrosine with 15.8% and 14.3% overall yield respectively.
Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China. chenxc@scu.edu.cn.
Hao
H
Liu
Ruijiao
R
Chen
Xiaochuan
X
Chen
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D008968:Molecular Conformation; D013237:Stereoisomerism; D013696:Temperature; D044005:Tetrahydroisoquinolines / Q000737:chemistry*
D000470:Alkaloids; D044005:Tetrahydroisoquinolines; C507294:renieramycin G