Interplay of intra- and intermolecular H-bonding in a progressively solvated macrocyclic peptide.

Interplay Between Lithium Bonding and Halogen Bonding in F3CX•••YLi•••NCCN and F3CX•••NCCN•••LiY Complexes (X = Cl, Br; Y = CN, NC)

MP2 calculations with cc-pVTZ basis set were used to analyze intermolecular interactions in F3CX···YLi···NCCN and F3CX···NCCN···LiY triads (X = Cl, Br; Y = CN, NC) which are connected via halogen and lithium bonds. Those complexes with the role of LiY as halogen acceptor and lithium donor show cooperativity with energy values ranging between -1.97 and -2.92 kJ mol...

Inductive Effect of Bioactive Intermolecular Hydrogen Bonding Complex of 1,2,4,5 –Tetrazine and Inorganic Acid by NMR and QTAIM

In this paper, NMR and QTAIM analysis for three substituted of T2SA complex was investigated in the gas and four solvents at DFT level. Intermolecular O–H…N hydrogen bonds between 1,2,4,5-Tetrazine and Sulphurous acids enhance the stability of complex.1,2,4,5-Tetrazine is a highly reactive diene for [4+2] inverse-Diels–Alder cycloaddition processes and an excellent precursor to attain the pyrid...

Ab Initio Quantum Chemical Studies of 15N and 13C NMR Shielding Tensors in Serine and Complexes of Serine- nH2O: Investigation on Strength of the CαH…O Hydrogen bonding in the Amino Acid Residue.

In this paper, the hydrogen bonding (HB) effects on the NMR chemical shifts of selected atoms in serineand serine-nH2O complexes (from one to ten water molecules) have been investigated with quantummechanical calculations of the 15N and 13C tensors. Interaction with water molecules causes importantchanges in geometry and electronic structure of serine.For the compound studied, the most importan...

Computational study of the intramolecular proton transfer between 6-hydroxypicolinic acid tautomeric forms and intermolecular hydrogen bonding in their dimers

This paper is a density functional theory (DFT) calculation of intramolecular proton transfer (IPT) in 6-hydroxypicolinic acid (6HPA, 6-hydroxypyridine-2-carboxylic acid) tautomeric forms. The transition state for the enol-to-keto transition is reported in the gas phase and in four different solvents. The planar and non-planar dimer forms of 6HPA keto and enol, respectively, were also studied i...

Computational study of three dimensional potential energy surfaces in intermolecular hydrogen bonding of cis-urocanic acid