The alkaloidal fraction of Alstonia scholaris leaves shows anti inflammatory and analgesic bioactivity in two A phytochemical study on this fraction led to the isolation of two novel alkaloids scholarisine I and (+/-)-scholarisine II Their structures were elucidated on the basis of spectroscopic methods and a possible biogenesis is proposed (+/-) Scholarisine II selectively inhibited the inducible COX-2 rather than COX-1 and also markedly inhibited 5-LOX comparable to positive controls