Substituted 5-alkynyl 1,2,3-triazoles

Keywords Alkyl halides, alkynes, sodium azide, CU2O, methanol, room temperature, multi-component reaction, click synthesis, heterocycles, substituted 5-alkynyl 1,2,3-triazoles... 

As another example, poly(glycolide)s have been described that include a polymeric alkynyl-substituted glycoUde (56). The alk-ynyl groups provide reactive sites for further functionalization of the polymer, for example by reaction with azide derivatives. The alkynyl and azide groups react via the click chemistry mechanism to form functional groups covalently bonded to the polymer via a triazole link. The polymers are biodegradable and can be used to deliver drugs or other therapeutic substances at controlled release rates. 

The alkynyl functionality of alkynones 1 is perfectly suited for subsequent copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) in the sense of an MCR (2015ASC(357)617). A microwave-assisted three-component reaction of aroyl chlorides 4, TMS-substituted acetylene (5a), and benzyl azide (10a) consisting of modified Sonogashira cross-coupling I, desilylation, and CuAAC furnishes 4-disubstituted 1,2,3-triazoles 11 in moderate to excellent yields (Scheme 5) (201 OOL(12)4936). 

Diastereoselective synthesis of cyc/o-saligenyl nucleoside phosphotriesters has been achieved using two diastereopure 3-methyl-cyc/o-Sal-phospho-triesters, e.g. (1, nucleoside phosphotriester derivatives of AZT and d4T were prepared and it was found that the antiviral activity was between five and 20-fold different between the individual diastereoisomers. A series of C5-substituted alkenyl- alkynyl- and aryl-dUMP derivatives was synthesised and assayed against the flavin-dependent thymidylate synthase ThyX from Mycobacterium tuberculosis. Of these some were found to be active at submicromolar concentration with specificity for ThyX compared with a bacterial thymidylate synthase. Eleven triazole nucleoside monophosphates (2) were synthesised, with inhibitory effects against bacterial NAD-dependent malic enzyme. ... 

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