http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/557 2025-10-30T07:59:33Z 2025-10-30T07:59:33Z Vanlaldinpuia, K http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/998 2025-10-16T10:39:46Z 2010-02-06T00:00:00Z

Title: An Excellent Method for Cbz-protection of Amines Authors: Vanlaldinpuia, K Abstract: Cbz-protection of aliphatic and aromatic amines can be accomplished with benzylchloroformate using a catalytic amount of dodecatungstophosphoric acid hydrate (0.05 equiv). The reaction is simple, fast, does not require aqueous work-up and gives excellent yields

2010-02-06T00:00:00Z Vanlaldinpuia, K http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/997 2025-10-16T10:37:59Z 2017-09-03T00:00:00Z

Title: Enantioselective aminocatalysis: Michael addition of unactivated ketones to nitroolefins catalyzed by D-fructose derived monofunctional primary amine Authors: Vanlaldinpuia, K Abstract: Organocatalytic asymmetric Michael addition is considered among the most extensively studied, yet challenging stereoselective reactions due to the fact that the electrophilic prochiral carbon in Michael acceptor lies away from stereodirecting groups of the catalyst. Although there is a report on stereoselective organocatalysis in Michael addition employing monofunctional secondary amine, the use of monofunctional primary amine for the said reaction is not reported till date. In fact, no monofunctional aminocatalyst is reported yet for the synthesis γ-nitro carbonyl compounds. Here we report our preliminary results on the enantioselective Michael addition of different ketones to nitro olefins catalysed by monofunctional primary amine (1) derived from d-fructose

2017-09-03T00:00:00Z Vanlaldinpuia, K http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/993 2025-10-16T10:30:09Z 2024-07-02T00:00:00Z

Title: Screening of novel carbohydrate-derived thioureas for antibacterial activity Authors: Vanlaldinpuia, K Abstract: Compounds synthesized from carbohydrate substrates have yielded promising lead molecules for pharmaceutical developments, as many are approved for the clinical management of a wide range of diseases. Among them, thiourea moieties are the gold mines of antibacterial molecules. In view of the lack and need for new antibiotics, a series of 16 D-fructose-based thiourea compounds were synthesized from asymmetric aldol reaction and isopropylidenation. The new compounds were established from nuclear magnetic resonance, Fourier-transform infrared, and electrospray ionization mass spectrometry. Using disk diffusion assay for antibiotic susceptibility, four of the novel compounds were found to have concentration-dependent antibacterial activities. The addition of trifluoromethyl groups at the meta-position on the phenyl ring of the thioureas appeared to promote bacterial inhibitory action. Thiourea 2a exhibited the most potent activity against the Gram-negative species, Klebsiella pneumoniae, Escherichia coli, and Salmonella typhi, as well as the Gram-positive species, Micrococcus luteus; but not against all bacteria tested. Thiourea 2b and 3a had lower efficacy but showed better broad-spectrum activity against most bacteria tested. Thiourea 3b displayed species-specific activity only against K. pneumoniae and S. typhi. Our findings show the benefits and prospects of synthesizing new carbohydrate compounds for therapeutic medication.

2024-07-02T00:00:00Z Vanlaldinpuia, K http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/987 2025-10-16T10:16:40Z 2011-05-12T00:00:00Z

Title: Useful methods for the synthesis of isopropylidenes and their chemoselective cleavage Authors: Vanlaldinpuia, K Abstract: A catalytic amount of phosphotungstic acid (PTA) has been found to be a very effective catalyst for isopropylidenation of 1,2-diols and their deprotection at room temperature. The ease of handling, cost and activity of the catalyst, good to excellent yields and chemoselectivity for deprotection are some of the highlights of the reported method.

2011-05-12T00:00:00Z