Five decades in the study of natural products

This paper describes the five-decade long fascinating journey taken by Prof. T R Govindachari towards the study of the natural products of India. A variety of Indian plants were investigated by him for the study of their constituent alkaloids and terpenoids. The concluding part of the paper summarizes the isolation and identification of the constituents of the Neem kernel, which eventually led to the first X-ray structure determination of azadirachtin A.