Susheel Durani

Cis isomer of centchroman — A selective ligand for the microsomal antiestrogen binding site

Several compounds structurally related to the triarylethylene antiestrogens, but possessing weak estrogen receptor affinities, were assessed for their ability to interact with the microsomal antiestrogen binding site. While all the compounds tested did interact with this site their relative affinities were somewhat lower than that of tamoxifen. One of these, viz., the cis isomer of centchroman, has however emerged as a selective ligand for the antiestrogen binding site since its estrogen receptor affinity is nearly 50,000 times lower on a relative scale.

A novel rearrangement reaction: single-step conversion of 2-(6-carboxy-3-oxoheptyl)-3,4-dihydro-6-methoxynaphthalen-1 (2H)-one into 1-(3-carboxybutyl)-2-(2-carboxyethyl)-3,4-dihydro-6-methoxynaphthalene

The synthesis of 2-(2-carboxyethyl)-1-(3-carboxypropyl)-3,4-dihydro-6-methoxynaphthalene (28) and the homologous diacid (30) has been achieved in a single step from the 2-(6-carboxy-3-oxoalkyl)-3,4-dihydro-6-methoxynaphthalen-1(2H)-ones (22) and (24), respectively, via a novel acid-catalysed cyclisation–rearrangement reaction. The structure of the diacids (28) and (30) is supported by the high resolution mass spectrometric data of their respective dimethyl esters (29) and (31). The aromatic methoxy-group and the carboxy-function at C-6 in the side chain are critical for the rearrangement, but not for the cyclisation, part of the reaction. Based on this and other observations a mechanism for this novel rearrangement reaction has been proposed.