Synthesis and exploration of anticancer potential of spirocyclic 1,2,3-triazoline and aziridine derivatives of natural eudesmanolide isoalantolactone.

Eudesmane-type sesquiterpene lactone isoalantolactone 1 is of great interest due to its availability, biological activity and synthetic application. Respective series of original spirocyclic (11S,5') (1,2,3-triazoline-eudesma-4,15-enolides) and (11S)-aziridine-eudesma-4,15-enolides were efficiently synthesized via a chemoselective 1,3-dipolar cycloaddition reaction of organic azides to the exocyclic double bond of the lactone ring of isoalantolactone or 13E-(aryl)isoalantolactones by heating in DMF or toluene. The thermal reactions of isoalantolactone with benzyl azide, 2-azidoethanol, or n-butyl azide in 2-methoxyethanol afforded 13-(alkyamino)isoalantolactones formed as a mixture of (Z) and (E)-isomers.

Design, Synthesis and Assay of Novel Methylxanthine-Alkynylmethylamine Derivatives as Acetylcholinesterase Inhibitors.

Xanthine derivatives have been a great area of interest for the development of potent bioactive agents. Thirty-eight methylxanthine derivatives as acetylcholinesterase inhibitors (AChE) were designed and synthesized. Suzuki-Miyaura cross-coupling reactions of 8-chlorocaffeine with aryl(hetaryl)boronic acids, the CuAAC reaction of 8-ethynylcaffeine with several azides, and the copper(I) catalyzed one-pot three-component reaction (A-coupling) of 8-ethynylcaffeine, 1-(prop-2-ynyl)-, or 7-(prop-2-ynyl)-dimethylxanthines with formaldehyde and secondary amines were the main approaches for the synthesis of substituted methylxanthine derivatives (yield 53-96%).