Synthesis and Human Anticancer Cell Line Studies on Coumarin-beta-carboline Hybrids as Possible Antimitotic Agents

A series of coumarin tetrahydro-beta-carboline hybrids 3 have been synthesized by the Pictet-Spengler reaction. Stoichiometrically controlled DDQ oxidation has led to dihydro 4 and beta-carboline 5. In vitro anticancer activity against 60 cell lines has revealed the potency of 3f, 4a and 5c. In silico studies indicate the binding properties of 5c with Kinesin spindle protein (KSP) and tubulin protein. Gel electrophoresis studies revealed that compound 3f partially cleaved the CT-DNA, whereas the ring C aromatized compound 5c completely cleaved the CT-DNA. Structures of the newly synthesized compounds are confirmed by spectroscopic and X-ray studies.