Jaimala Sharma

Mild and Ecofriendly Tandem Synthesis, and Spectral and Antimicrobial Studies of N1-Acetyl-5-aryl-3-(substituted styryl)pyrazolines

N1-acetyl-5-aryl-3-(substituted styryl)pyrazolines were synthesized by the cyclocondensation of 1,5-substituted diphenyl-1,4-pentadien-3-ones with hydrazine hydrate and a cyclizing agent such as acetic acid in ethanol. The title compounds were synthesized using conventional and solvent-free approaches, which involves mechano-chemical mixing, microwave-irradiation, and ultrasound-irradiation methods in the presence of a solid support. The synthesized compounds have been characterized by elemental analyses and spectral data (IR, PMR, and FAB-mass). All the synthesized compounds have been evaluated for their antibacterial and antifungal activities. Some compounds have shown promising biological activity.

Synthesis and Characterization of a New Class of Benzothiazolines

Abstract A new class of benzothiazolines having the composition, C(OH)COOCH 3 [where R = C 6 H 5 , 4-BrC 6 H 4 , 4-ClC 6 H 4 , 4-CH 3 OC 6 H 4 , 4-CH 3 C 6 H 4 ] have been synthesized by the equimolar condensation of aroyl pyruvates, RC(O)CH:C(OH)COOCH 3 with 2-aminothiophenol. These newly synthesized benzothiazolines have been characterized by elemental analyses and spectral [IR and NMR ( 1 H and 13 C)] studies.

Photochemical synthesis of novel 4,5,9,10-tetraaryl-tricyclo[6.2.0.03,6]decane-2,7-diones: a theoretical view of photodimerization

A sequence of photodimerization reactions of 1,5-diaryl-1,4-pentadien-3-ones have been carried out to produce 4,5,9,10-tetraaryl-tricyclo[6.2.0.03,6]decane-2,7-diones. The title compounds were characterized by means of infrared (IR), nuclear magnetic resonance (NMR) and mass spectrometric methods. The reaction proceeds via a diradical stepwise mechanism through the triplet excited state with asynchronous ring closure. Density functional theory calculations have been well established to probe the mechanism of photodimerization. The diradical mechanism for dimerization of chalcone proceeds via ring closure of the complex formed by two molecules.

Synthesis and Characterisation of Additional Products of Phenylarsenic(III) Dimethoxide With Substituted Benzothiazolines

Phenylarsenic(III) dimethoxide derivatives of substituted benzothia-zolines having the general formula PhAs(OMe) 2 where R = CH 3 , R′ = CH 3 (1), R = C2H5, R′ = C2H5 (2), R = H, R′ = C6H5 (3), R = CH 3 , R′ = C6H5 (4) R = CH3, R′ = C6H4CH3-4 (5), R = CH3, R′ = C6H4Cl-4 (6), have been synthesized by the reaction of PhAs(OMe)2 (prepared in situ) with substituted benzothiazolines in a 1:1 molar ratio in refluxing benzene solution. These newly synthesized complexes have been characterized by elemental analysis and molecular weight measurements. The spectral studies IR, 1 H, and 13 C NMR show the formation of the additional products in which the nitrogen atom of the benzothiazoline-ring coordinate to the central arsenic atom. A distorted trigonal bipyramidal geometry around arsenic atom has been tentatively proposed for these derivatives.