Synthesis and antiviral activity of novel exomethylene cyclopropyl nucleosides

Design, synthesis, antibacterial evaluation, molecular docking and computational study of 4-alkoxy/aryloxyphenyl cyclopropyl methane oxime derivatives

A series of new 4-alkoxy/aryloxyphenyl cyclopropyl methane oxime derivatives 2(a-k) were synthesized and fully characterized by FT-IR, 1H-NMR, 13C-NMR and Mass spectrometry techniques. All the synthesized compounds 2(a-k) were assayed for in vitro antibacterial activity against a selected bacterial strain and the compound (2 h) and (2k) exerted excellent activity against Staphylococcus aureus, Escherichia coli and Salmonella typhi strains. The potency of inhibitors and possible interaction mechanism of synthetic oxime (2k) with 1GQN enzyme on Salmonella typhi was explored by molecular docking method. Amongst the all synthesized compounds, the quantum chemical calculations were done for Cyclopropyl(4-(pyridin-3-ylmethoxy)phenyl)methanone oxime (2k). The first hyperpolarizability calculation performed in different solvent such as CHCl₃, CH₂Cl₂ and DMSO and compared to the reference compound urea. In addition, natural bond orbital analysis (NBO), local reactivity descriptors, thermodynamic properties, Mulliken charges, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were explored using theoretical calculations.

Synthesis of 2,2,3-tris(hydroxymethyl)methylenecyclopropane analogues of nucleosides

Synthesis of 2,2,3-tris(hydroxymethyl)methylenecyclopropane analogues 16a, 16b, 17a, and 17b is described. Diethyl ester of Feist's acid 18b was hydroxymethylated via carbanion formation using formaldehyde under simultaneous isomerization to cis diester to give intermediate 19. Reduction followed by acetylation gave triacetate 22. Addition of bromine afforded reagent 23, which was used for alkylation-elimination of adenine and 2-amino-6-chloropurine to provide Z,E-isomeric mixtures of 24a and 24b. Deacetylation and separation furnished the Z-isomers 16a, 16c and E-isomers 17a, 17c. Hydrolytic dechlorination of 16c and 17c gave guanine analogues 16b and 17b. None of the analogues exhibited a significant antiviral activity. Adenosine deaminase is refractory toward adenine analogues 16a and 17a.