Preparation of 17‐amino‐22‐(4′‐azido‐3′‐125iodophenacyl)‐17‐demethoxygeldanamycin (1): An ansamycin for photoaffinity labeling

Abstract

An azido‐¹²⁵iodo‐ansamycin (1) in the geldanamycin family was prepared in two steps in one reacton vessel from 17‐amino‐22‐(4′‐aminophenacyl)‐17‐demethoxygeldanamycin (3). The title compound was suitable for photoaffinity labeling proteins that interacted with ansamycins. A alternative synthesis is reported for preparation of unlabeled title compound in order to afford practical amounts of (1) for conventional biochemical studies.