Dr (Mrs) Chatterjee has built up an active school of advanced study and research in the chemistry of natural products, especially in the chemistry of alkaloids and coumarins, including furanolactones isolated from medicinal plants indigenous to India. She has investigated 50 plant species of 12 botanical families from which she isolated 20 new alkaloids, 5 polyphenolics, of which 3 are coumarins and two dianthraquinones, besides several furanoid bitter principles and an antiepileptic long chain ester. These researches are characterized by novel techniques for the isolation of organic compounds from plant sources, elucidation of their molecular architecture and stereochemistry by classical and modern methods, including spectroscopy, their synthesis, biogenesis and chemotaxonomy, the latter study being undertaken to trace the path of biological evolution. The alkaloids isolated by her are of novel structural patterns belonging to monomeric and dimeric indole groups, to quinoline, isoquinoline, pyridine, diterpene and steroidal series. She has also made notable contribution to organic reactions by postulating a new mechanism. She and her colleagues have conducted intensive physiological, pharmacological and clinical studies on natural and synthetic organic chemicals. Their work on the tranquillising alkaloids of Rauvolfia, particularly Rauvolfia canescens, in the treatment of insomnia and hypertension, and on Alstonia alkaloids in curing cardiac disorder, deserves special mention.