Postassembly Modification of Peptides by Histidine-Directed ß-C(sp3)-H Arylation of Alanine at the Internal Positions: Overcoming the Inhibitory Effect of Peptide Bonds.

Peptide modification by C(sp3)-H functionalization of residues at the internal positions remains underdeveloped due to the inhibitory effect of backbone amides. In this study, using histidine (His) as an endogenous directing group, we developed a novel method for the ß-C(sp3)-H functionalization of alanine (Ala) at diverse positions of peptides. Through this approach, a wide range of linear peptides were modified on the side-chain of Ala adjacent to His to afford the functionalized peptides in moderate to good yield and excellent position selectivity. Furthermore, conjugation of peptides with functional molecules such as glucuronide, oleanolic acid, dipeptide, and fluorophore derivatives was achieved.

Dataset on biochemical inhibiting activities of selected phytochemicals in Azadirachta indica L as potential NS2B-NS3 proteases inhibitors.

The anti-NS2B-NS3 proteases activities of Azadirachta indica L. were investigated via the data obtained from selected bioactive compounds from Azadirachta indica L. The work was investigated using insilico approach and the series of computational software were used to execute the task. The software used were Spartan 14, material studio, Padel, Pymol, Autodock tool, Autodock vina and discovery studio. The obtained descriptors from 2D and 3D of the optimized compounds were screened and they were used to develop QSAR model using material studio software. Also, biological interaction between the selected bioactive compounds from Azadirachta indica L. and NS2B-NS3 proteases (PDB ID: 2fom) were accomplished using docking method and the calculated binding affinity as well as the residues involved in the interaction were reported. More so, the ADMET features for [(5S,6R,7S,8R,9S,10R,11S,12R,13S,17R)-17-(2,5-dihydroxy-2,5-dihydrofuran-3-yl)-11,12-dihydroxy-6­methoxy-4,4,8,10,13-pentamethyl-1,16-dioxo-6,7,9,11,12,17-hexahydro-5H-cyclopenta[a]phenanthren-7-yl] 3-methylbut-2-enoate (Compound 6) and (10R,13S,14S,17S)-17-[1-(3,4-dihydroxy-5,5-dimethyloxolan-2-yl)ethyl]-4,4,10,13,14-pentamethyl-1,2,5,6,9,11,12,15,16,17-decahydrocyclopenta[a]phenanthren-3-one (compound 12) with lowest binding affinity were investigated and reported.

Post-Assembly Modification of Peptides by Ligand-Enabled ß-C(sp3)-H Arylation of Alanine at the C-Terminus: Overcoming the Inhibition Effect of Peptide Bonds.

Postassembly modification of peptides via C(sp3)-H functionalization on aliphatic side chains provides a straightforward approach to access functionalized peptides as therapeutics. However, C(sp3)-H functionalization of C-terminal residues remains underdeveloped due to the inhibition effect of secondary amides in the backbone. Herein, we report a ligand-enabled, bidentate auxiliary-assisted ß-C(sp3)-H arylation method, which is well tolerant of secondary amides. A wide range of peptides (tri- to dodecapeptides) underwent position-specific modification of alanine at the C-terminus.