Showing papers by "Hiroshi Yoshida published in 1990"
TL;DR: New cyclotetrapeptides, trapoxins A and B were isolated from the culture broth of Helicoma ambiens RF-1023 and exhibit detransformation activities against v-sis oncogene-transformed NIH3T3 cells (sis/NIH 3T3) as antitumor agents.
Abstract: New cyclotetrapeptides, trapoxins A and B were isolated from the culture broth of Helicoma ambiens RF-1023. These compounds exhibit detransformation activities against v-sis oncogene-transformed NIH3T3 cells (sis/NIH3T3) as antitumor agents. The structures were found to be new cyclotetrapeptides, cyclo[(S)-phenylalanyl-(S)-phenylalanyl-(R)-pipecolinyl- (2S,9S)-2-amino-8-oxo-9,10-epoxydecanoyl-] for trapoxin A and cyclo[(S)-phenylalanyl-(S)-phenylalanyl-(R)-prolyl-2- amino-8-oxo-9,10-epoxydecanoyl-] for trapoxin B, by X-ray analysis, mass spectrometric, NMR and chemical studies.
183 citations