Abstract
The aerial parts of Anisotes trisulcus L. (N. O. Acanthaceae) have afforded a new spiro quinazoline alkaloid, characterized as 4, 5, 7-trihydro-3, 2'-spiro-[(1'-oxolo)-benzopyr-3'-one]-pyrralo-[4, 5-b]-quinazoline by chemical and spectral methods and has been designated as trisulcusine 1. In addition, the previously reported alkaloids, namely, peganine 2, vasicinone 3 and 5-methoxypeganine 4 have also been isolated and characterized.