Collybial, a New Antibiotic Sesquiterpenoid from Collybia confluens (Basidiomycetes)

Abstract

A new antibiotic was isolated from fermentations of an american strain of Collybia confluens. Its structure was elucidated by spectroscopic methods as 2,10,10-trimethal-4-oxo-tricyclo[7.2.0.02.5]undec-6-en-carbaldehyde (with the relative stereo chemistry 1S, 2R, 5R, 9R) (1). The inhibitor, which was named collybial, is structurally related to koraiol, a sesquiter-penoid isolated from Pinus koraiensis (Khan V. A. (1979), Khim. Prir. Soedin 5, 652–658). Collybial inhibited the growth of Gram-positive bacteria at concentrations starting from 21.5 [μm. The propagation of vesicular stomatitis virus (VSV) in baby hamster kidney (BHK-21) cells was inhibited by 21.5 [μm collybial. Cytotoxic effects on BHK cells were observed at 5 fold higher concentrations. © 1995 Verlag der Zeitschrift für Naturforschung. All rights reserved.