gasp: a computer program to generate automatically polycyclic structures

We present a new program to generate a virtual library of structures. gasp (Génération Automatique de Structures Polycycliques) answers to a question like: generate all structures with 3 rings of size 4, 6 and 8 for example. We present the results obtained for ‘isomers’ of several structures (steroid, taxane and triquinane skeletons). For steroid skeleton (4 rings of size 6, 6, 6 and 5) 988 structures were generated. Among them 48 are composed of fused rings. Comparison with the Beilstein database showed that among these 48 structures 21 are new.