Boc-L-valine

Bio-compatible water-soluble conjugates of Co(II), Cu(II) and Zn(II) (1-3), [Co(Boc-L-valine) 2 (imidazole) 2 ], [Cu(Boc-L-valine) 2 (imidazole) 2 ], and [Zn(Boc-L-valine) 2 (imidazole) 2 ], were synthesized and comprehensively characterized by various spectroscopic techniques (UV-visible, FT-IR, ESI-MS, EPR, 1 H NMR, 13 C NMR) and single crystal X-ray diffraction which showed that the complexes 1-3 crystallized in an orthorhombic crystal system, in a slightly distorted octahedral geometry having the space group P 2 1 2 1 2. Density functional theory calculations were performed to correlate the energy of frontier molecular orbitals with the stability and reactivity of the complexes. In vitro DNA binding interaction studies of complexes were performed by employing various biophysical techniques and their corroborative results revealed (i) the electrostatic mode of binding in the groove region of DNA, (ii) pBR322 plasmid cleavage at a low concentration of 5-12.5 μM via an oxidative pathway in complexes 1 and 2 and the hydrolytic mechanism in the case of 3, (iii) changes in the 1 H NMR chemical shift values of the NH 2 group of GMP after interaction with complex 3, (iv) alteration in the EPR parameters of complex 2 after complexation with DNA, (v) SOD mimetic activity of complex 2 with the IC 50 value of 2.08 μM and (vi) a good and selective cytotoxicity profile against chemo-resistant MCF-7 and MDA-MB-231 cancer cell lines by complex 1. Molecular docking studies complemented the spectroscopic results and confirmed the electrostatic interaction of complexes in the groove region of DNA.

Huanglongbing (HLB) is a worldwide citrus plant disease-related to non-culturable and fastidious α-proteobacteria Candidatus Liberibacter asiaticus (CLas). In CLas, Peroxiredoxin (Prx) plays a major role in the reduction of the level of reactive species such as reactive oxygen species (ROS), free radicals and peroxides, etc. Here, we have used structure-based drug designing approach was used to screen and identify the potent molecules against 2Cys Prx. The virtual screening of fragments library was performed against the three-dimensional validated model of Prx. To evaluate the binding affinity, the top four molecules (N-Boc-2-amino isobutyric acid (B2AI), BOC-L-Valine (BLV), 1-(boc-amino) cyclobutane carboxylic acid (1BAC), and N-Benzoyl-DL-alanine (BDLA)) were docked at the active site of Prx. The molecular docking results revealed that all the identified molecules had a higher binding affinity than Tert butyl hydroperoxide (TBHP), a substrate of Prx. Molecular dynamics analysis such as RMSD, Rg, SASA, hydrogen bonds, and PCA results indicated that Prx-inhibitor(s) complexes had lesser fluctuations and were more stable and compact than Prx-TBHP complex. MMPBSA results confirmed that the identified compounds could bind at the active site of Prx to form a lower energy Prx-inhibitor(s) complex than Prx-TBHP complex. The identified potent molecules may pave the path for the development of antimicrobial agents against CLA.Communicated by Ramaswamy H. Sarma.

We presented a general and facile strategy to prepare biocompatible multiamino polymers. Series of new monomers were synthesized by esterification of 2-hydroxyethyl methacrylate (HEMA) and Boc-amino acids, such as Boc-l-phenylalanine, Boc-glycine, Boc-l-alanine, Boc-l-valine, and Boc-l-lysine. Subsequent vinyl polymerization of monomers gave rise to vinyl poly(amino acid)s with a side primary amino group at each unit if deprotected. Both atom transfer radical polymerization (ATRP) and conventional free radical polymerization (FRP) were employed to prepare the multiamino polymers. A well controlled effect upon molecular weight with the standard first-order kinetics was achieved in cases of ATRP, and high molecular weight polymers were obtained via FRP. MTT assay showed that cell survival rates for the multiamino polymers were almost maintained above 90% and that their cytotoxicities were much lower than that of linear PEI (PEI 25000). Zeta potential measurements demonstrated that the vinyl poly(amino acid)s are electropositive, and AFM measurements showed that the vinyl poly(amino acid)s could tightly condense DNA into granular structures at a suitable concentration. The combination of facile availability, controlled productivity, low cytotoxicity and strong binding ability with DNA promises the great potential of the novel multiamino polymers in bioapplications.