DFT and MP2 study of low barrier proton transfer in hydrazide schiff base tautomers via water bridges and in the gas

Design and synthesis of novel quinazolinone-based derivatives as EGFR inhibitors with antitumor activity

Nineteen new quinazolin-4(3H)-one derivatives 3a–g and 6a–l were designed and synthesised to inhibit EGFR. The antiproliferative activity of the synthesised compounds was tested in vitro against 60 different human cell lines. The most potent compound 6d displayed superior sub-micromolar antiproliferative activity towards NSC lung cancer cell line NCI-H460 with GI₅₀ = 0.789 µM. It also showed potent cytostatic activity against 40 different cancer cell lines (TGI range: 2.59–9.55 µM). Compound 6d potently inhibited EGFR with IC₅₀ = 0.069 ± 0.004 µM in comparison to erlotinib with IC₅₀ value of 0.045 ± 0.003 µM. Compound 6d showed 16.74-fold increase in total apoptosis and caused cell cycle arrest at G1/S phase in breast cancer HS 578T cell line. Moreover, the most potent derivatives were docked into the EGFR active site to determine their binding mode and confirm their ability to satisfy the pharmacophoric features required for EGFR inhibition.

Infrared Fingerprints of nN → σ*NH Hyperconjugation in Hydrazides

An earlier study demonstrated that hyperconjugation operates in hydrazides by analyzing the N-H stretching mode in gas phase infrared (IR) spectroscopy, and then observing two very distinct bands corresponding to isolated isomers experiencing or not the n_N → σ*_N-H electron delocalization. The present work reports a chemical method to obtain insight on the hyperconjugation in hydrazide derivatives from solution IR spectroscopy. The analogous amides did not show a ν_N-H red-shifted band, as the electron donor orbital in the above hyperconjugative interaction does not exist. In addition, the effect of electron withdrawing groups bonded to a nitrogen atom, namely the trifluoroacetyl and the methanesulfonyl groups, was analyzed on the conformational isomerism and on the ability to induce a stronger hyperconjugation in the resulting compounds.