A new and efficient preparation of pharmacologically and biologically important 2,5-disubstituted 6-azaindoles was achieved from cyclizations of aziridin-2-yl dipropargylic alcohols as adducts of two propargyl groups to ethyl 1-benzylaziridine-2-carboxylate. The sequential cyclizations include pyrrole formation and a novel base-catalyzed intramolecular acetylenic Schmidt reaction.

Synthesis of a 9-membered azaenediyne has been achieved for the first time via intramolecular N-alkylation; the importance of proximity of the reacting centres via cobalt carbonyl complexation of the acetylenic moiety and not the activation of propargylic carbon has been demonstrated.

The gold(I)-catalyzed carboalkoxylation of alkynes to form indanone derivatives from readily available ortho-acetylenic benzylic ethers is described. Importantly, the gold(I)-catalyzed rearrangement of enantioenriched benzylic ethers proceeds with chirality transfer, thus providing a practical method for the enantioselective synthesis of indenyl ethers.

A shape-persistent alleno-acetylenic macrocycle, peripherally decorated with eight phenolic rings, has been synthesized in enantiomerically pure form. Its electronic circular dichroism spectrum features a strong chiroptical response. In the solid state, the macrocycle stacks in pillars to form channels and the stacks undergo further self-assembly into a three-dimensional porous architecture thr...

We report the formation of a highly unusual fused, tricyclic purine derivative via N3 alkylation of 9-propargyladenine, upon activation of the acetylenic triple bond by Ag(I) ions. The participation of silver ions in this process might offer newer design paradigms for minor groove N3 DNA alkylation, antibacterial and anticancer agents.