| abstract |
Sesquiterpenes of formula (I), wherein each of a and b is a single bond or one is a single bond and the other is a double bond; A, together with a, b and the carbon atoms to which it is attached forms a ring selected from: (a); (b) wherein R is H or OH; (c); and (d); and Y is a double bond or, when A is a ring (a) as defined above Y is either a double bond or forms, together with the carbon atoms to which it is attached, an epoxide linkage @ obtainable from the fungal strain Acremonium strictum X06/15/458, and pharmaceutically and veterinarily acceptable salts thereof, are inhibitors of the binding of benzodiazepine to the GABA-benzodiazepine-C1 ionophore receptor complex. These compounds are prepared by (i) fermenting, in a source of carbon, nitrogen and inorganic salts, fungal strain X06/15/458 (IMI 354451) or a mutant thereof which produces the said sesquiterpenes, (ii) isolating the sesquiterpenes from the fermentation medium; and (iii) if desired, converting the said sesquiterpene into a pharmaceutically or veterinarily acceptable salt thereof. <IMAGE> |