Based on modeling studies, we hypothesized that tylosin derivatives without formyl group should rather adopt an erythromycin-like binding mode to the ribosome. Twenty four 16-membered macrocyclic compounds were accessed by multicomponent reactions (Gewald, Ugi) of tylosin and investigated for their antituberculosis activity. The best compound was twice as active as tylosin and might thus be a good starting point for further optimization of biological properties.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Three useful sets of reaction conditions (portionwise or syringe pump addition of catalytic Bu3SnH and photolysis with catalytic hexabutyltin) are given for the cyclization of hex‐5‐ynyl iodides such as (I) to (iodomethylene)cyclopentanes such as (II).

Two variants are described for the preparation of cyclopentanes such as (II) or (IV) via a radical cyclization procedure, involving halogen abstraction, 1,5‐H atom transfer, cyclization and chain transfer.

The radical‐induced cyclization of the 6‐iodohexenes (I) yields the iodomethylcyclopentanes (III).