An overview of general classification scheme, medicinal importance and crystal structure analysis with emphasis on the role of hydrogen bonding in some alkaloids is presented in this paper. The article is based on a general kind of survey while crystallographic analysis and role of hydrogen bonding are limited to only those alkaloids whose three-dimensional structure has been reported by us. Th...

Copper complexes of the phenolic oxime family of ligands (3-X-salicylaldoximes) are used extensively as metal solvent extractants. Incorporation of electronegative substituents in the 3-position, ortho to the phenol group, can be used to buttress the interligand H-bonding, leading to an enhancement in extractant strength. However, investigation of the relevant H-bonding in these complexes can b...

The asymmetric unit of the title compound, C(8)H(12)O(3), consists of a single conformational enanti-omer, which aggregates in the catemeric acid-to-ketone hydrogen-bonding mode [O⋯O = 2.682 (4) Å and O-H⋯O = 172 (6)°]. Four hydrogen-bonding chains of translationally related mol-ecules pass through the cell orthogonal to the 4(3) screw axis along c, alternating in the 110 and the 10 direction, ...

In the title compound, {[Cu(C(5)H(6)O(4))(ClO(4))(C(16)H(22)N(4))]ClO(4)·2H(2)O}(n), square-pyramidally coordinated Cu atoms with perchlorate and dimethyl-malonate ligands are connected into cationic sinusoidal coordination polymer chains by doubly protonated bis-(3-pyridylmeth-yl)piperazine (3-bpmp) ligands. The chains aggregate into pseudo-layers parallel to the (101) crystal planes by N-H⋯O ...

In the title compound, (C(20)H(17)N(2))(2)[Pd(2)Cl(6)]·2C(6)H(6), the dichloride-bridged [Pd(2)Cl(6)](2-) anion lies across an inversion center with each Pd(II) ion in a slightly distorted square-planar environment. In the crystal structure, two cations and an anion are connected via N-H⋯Cl hydrogen bonds between the NH groups of the iminioisoindoline cations and terminal Cl atoms of a hexa-chl...

The title compound, C(15)H(15)N(3)O(2), contains benzonitrile and 4,4-dimethyl-2,6-dioxocyclo-hexyl-idene groups connected via a hydrazinyl group. The structure is in the hydrazone tautomeric form in the solid state. The benzonitrile and hydrazinyl groups (3-hydrazinylbenzonitrile) are essentially coplanar with an r.m.s. deviation of 0.016 Å. Intra-molecular N-H⋯O hydrogen bonding helps to stab...

In the crystal structure of the title compound, [Cu(2)(C(2)H(3)O(2))(4)(C(12)H(12)N(2))(2)], the binuclear mol-ecule lies about a center of inversion; the four acetate groups each bridge a pair of Cu(II) atoms. The coordination of the metal atom is distorted square-pyramidal, with the bonding O atoms comprising a square basal plane and the coordinating N atom of the N-heterocycle occupying the ...

An organocatalytic strategy for the synthesis of tetrasubstituted pyrrolidines with monoactivated azomethine ylides in high enantiomeric excess and excellent exo/endo selectivity is presented. The key to success is the intramolecular activation via hydrogen bonding through an o-hydroxy group, which allows the dipolar cycloaddition to take place in the presence of azomethine ylides bearing only ...

The title compound, C(18)H(16)O(7)·H(2)O, is a flavonoid isolated from Dodonaea viscosa-. The benzopyran ring system of the flavonoid is essentially planar [maximum deviation = 0.025 (2) Å] and inclined at 5.83 (2)° to the attached benzene ring. The water of hydration is involved in extensive hydrogen bonding, assembling the mol-ecules into a supra-molecular network via classical inter-molecula...

In the title compound, C(13)H(11)BBrFO(3), the dioxy-boron fragment is close to co-planar with the benzene ring to which the B atom is connected [dihedral angle = 8.96 (4)°]. The dihedral angle between the two benzene rings is 14.8 (2)°. One of the OH groups is engaged in an intra-molecular O-H⋯O hydrogen-bonding inter-action. The second OH group is involved in inter-molecular hydrogen bonding,...