Synthetic Studies on Ecteinascidin-743: Constructing a Versatile Pentacyclic Intermediate for the Synthesis of Ecteinascidins and Saframycins
作者:Wei Jin、Sammy Metobo、Robert M. Williams
DOI:10.1021/ol034575n
日期:2003.6.1
[reaction: see text] The asymmetric synthesis of a highly functionalized pentacyclic tetrahydroisoquinoline relevant to the ecteinascidin, saframycin, safracin, and renieramycin family of antitumor alkaloids is described.
Expedient entry to the piperazinohydroisoquinoline ring system using a sequential Ugi/Pictet–Spengler/reductive methylation reaction protocol
作者:Ma.-Angeles Cano-Herrera、Luis D. Miranda
DOI:10.1039/c1cc10759c
日期:——
An expedient entry to the piperazinohydroisoquinoline ring system present in the tetrahydroisoquinoline antitumor alkaloids family is described. The synthetic sequence involves: a sequential Ugi reaction followed by an N-Boc-deprotection process and iminium formation with a spontaneous PictetâSpengler cyclization and reductive N-methylation, with all these processes performed in a two-operation protocol in the same reaction flask.
A simple and efficient synthesis of a variety of (Z) -3-arylidene-6-arylmethyl-2, 5-piperazine-diones 10 having highly oxygenated benzene rings, and regioselective benzylation at position 4 are described.