The structure of tryptanthrin, an antibiotic produced by the yeast Candida lipolytica has been determined by X-ray crystallographic analysis. The structure has been solved by direct methods and refined by block-diagonal least-squares to R 0·089 using 1207 independent reflections. The crystals are monoclinic, space group P21/c, with a= 7·46, b= 7·66, c= 20·78 Å; β= 109·0°, Z= 4. Tryptanthrin has thus been proved to be indolo[2,1-b]-quinazoline-6,12-dione: the structural features are consonant with the spectroscopic behaviour.
Krishnan SriramanMark J. NovakJ. Clayton BaumAndrew HerronJoel A. Olson
Ramu GudaSirassu NarsimhaRamavath BabuSrujana MuthadiHarikiran LingabathulaRambabu PalabindelaNarsimha Reddy YelluAshok KumarMamatha Kasula
Mark J. NovakJ. Clayton BaumJerry W. BuhrowJoel A. Olson
Fábio Luiz Paranhos CostaSidnei Bessa de Oliveira FernandesCatharina Eccard FingoloFábio BoylanGunar Vingre da Silva Mota