Alka Agarwal

Synthetic application of gold nanoparticles and auric chloride for the synthesis of 5-substituted 1H-tetrazoles

An effective one-pot, convenient gold catalyzed synthesis of 5-substituted 1H-tetrazoles has been discussed. The study demonstrated the comparative overview for utilization of gold(III) and gold nano-particles (spheres) as a catalyst. Detailed understandings of the mechanism, surface area effect (in reference to nanoparticles) of gold in the activation of nitriles for nucleophilic (3 + 2) cycloaddition of sodium azide to give the product have also been studied.

2-(4-Chloro-phen-yl)chromen-4-one.

The title compound, C15H9ClO2, is a synthetic flavonoid obtained by the cyclization of 3-(4-chlorophenyl)-1-(2-hydroxyphenyl)prop-2-en-1-one. The 4-chlorophenyl ring is twisted at an angle of 11.54° with respect to the chromen-4-one skeleton. In the crystal, pairs of molecules are interconnected by weak Cl⋯Cl interactions [3.3089 (10) Å] forming dimmers which are further peripherally connected through intermolecular C—H⋯O hydrogen bonds.

(2E)-1-(4-Amino­phen­yl)-3-(2,4-dichloro­phen­yl)prop-2-en-1-one

The title compound, C15H11Cl2NO, is approximately planar (r.m.s. deviation = 0.062 Å) and contains a single C=C double bond in a trans (E) configuration. The crystal packing is stabilized by intermolecular N—H⋯N and N—H⋯O intermolecular hydrogen bonding.

Benzyl N-(3-chloro-4-fluoro­phen­yl)carbamate

The title compound, C14H11ClFNO2, the phenyl ring (A), the chlorofluorophenyl ring (B) and the central ketone O/C/O group (C) are not coplanar, with dihedral angles B/C = 31.6 (2), A/B = 21.3 (2) and A/C = 50.1 (2)°. The crystal packing is stabilized by N—H⋯O and C—H⋯O interactions.

tert-Butyl N-{2-[bis-(prop-2-yn-1-yl)amino]-phen-yl}carbamate.

In the crystal of the title compound, C17H20N2O2, the molecules are linked by C—H⋯O interactions. Intramolecular C—H⋯O and N—H⋯N hydrogen bonds also occur.

In vivo antifilarial activity of some cyclic and acylic alcohols

The filarial nematodes, Wuchereria bancrofti, Brugia malayi, and Brugia timori are the causative agents of lymphatic filariasis. 2-Substituted propanol, cyclohexanol, and cyclooctanol compounds were evaluated for microfilaricidal and macrofilaricidal activity in vivo against Acanthocheilonema viteae and Litomosoides carinii in rodents. In the cyclohexanol series, 2-(piperidin-1-yl) cyclohexanol (2b) showed 88.9% macrofilaricidal activity against A. viteae in vivo, while cyclooctanol series, 2-(4-benzyl piperdin-1-yl) cyclooctanol (2f) showed 100% macrofilaricidal activity against A. viteae. Further, compounds 1-(furan-2-ylamino) ethanol (4a) and 1-(4-benzylpiperidin-1-yl)-ethyl acetate (5b) showed 81.3% and 83.4% macrofilaricidal activity, respectively, against the same parasite. Interestingly, compounds 2f and 4a showed significant sterilization of female worms in A. viteae. However, these compounds were found inactive against L. carinii. Therefore, the new class of compounds appeared to have promising antifilarial activity.

N-(Prop-2-yn-1-yl)-1,3-benzothia­zol-2-amine

In the title compound, C10H8N2S, the 2-aminobenzothiazole and propyne groups are not coplanar [dihedral angle = 71.51 (1)°]. The crystal structure is stabilized by strong intermolecular N—H⋯N hydrogen bonds and C—H⋯C, C—H⋯π and F-type aromatic–aromatic [centroid–centroid distance = 3.7826 (12) Å] interactions are also observed.

1-Prop-2-ynyl-1H-benzimidazol-2-amine.

In the title compound, C10H9N3, the benzimidazol-2-amine and CH2—C CH units are not coplanar, with a dihedral angle of 60.36° between their mean planes. The crystal structure is stabilized by intermolecular N—H⋯N hydrogen bonding and π–π interactions [centroid–centroid distances 3.677 (1) and 3.580 (1) Å], assembling the molecules into a supramolecular structure with a three-dimensional network.