Publications by authors named "Arup Bhowmik"
Article Synopsis
- - This study presents a reliable one-pot method for creating indole-3-carboxylic acids using isatins and DMSO, which involves a unique one-carbon shift that leads to specific chemical transformations.
- - The method can be adapted to produce anthranilic acid derivatives by adjusting reaction conditions with molecular oxygen.
- - The research also highlights how this technique can facilitate the synthesis of easily accessible pharmaceutical compounds, such as the drug tropisetron.
Article Synopsis
- * This approach uses a metal-free radical-radical cross-coupling reaction, making it efficient and compatible with various functional groups.
- * Research showed that sulfonyl radicals can be produced from sulfonyl hydrazides using TBHP in an oxygen-rich environment, aiding the reaction process.
Article Synopsis
- A new copper-catalyzed method allows for efficient direct silylation of benzamides, producing organosilane products in good yields.
- This approach uses readily available disilanes and a directing group called 8-aminoquinoline, making it straightforward and practical.
- It’s environmentally friendly, involving an earth-abundant metal and can accommodate various functional groups, as shown by successful gram-scale tests.
Activation of anthrone via benzylic deprotonation in the presence of triethylamine paves the way for the 1,2-addition reaction with imines to provide the desired functionalized anthrones in good to excellent yields under mild and operationally simple reaction conditions with a broad range of substrate scopes without using any external additives or toxic stoichiometric reagents.
View Article and Find Full Text PDFAn iridium-catalyzed ortho-selective C-H arylation of cyclic N-sulfonyl ketimines has been achieved with environmentally benign aryl siloxanes. The reaction is highly efficient and proceeds at ambient temperature which is the key feature of the methodology considering the weak coordination nature of the substrate as well as the sluggish reactivity of siloxanes. A wide array of pharmaceutically relevant novel biaryls has been synthesized under operationally simple conditions.
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- A new method using Rh(III) catalysis has been developed to create spirocycles by combining benzoxazines with nitroolefins through C-H functionalization.
- The reaction efficiently builds three stereogenic centers in a single step from easily obtainable achiral materials and uses mild conditions.
- This process results in a variety of pharmaceutically important nitro-substituted spirocyclic 2,3-dihydro-1,4-benzoxazine derivatives, achieving high yields and selectivity.
Article Synopsis
- Researchers developed a new reaction method using Ir(III) as a catalyst to combine certain types of N-sulfonyl ketimines and α, β-unsaturated nitro olefins.
- This process is unique because it creates three different stereogenic centers in one step through direct C-H functionalization, which is typically challenging.
- The method successfully produced a variety of nitro-substituted spirocyclic benzosultams with high yields and good diastereoselectivity, using readily available starting materials.
Human papillomavirus (HPV) has been recently associated with squamous cell carcinoma of upper aerodigestive tract (SCC of UADT), but its possible role in promoting aberrant methylation in these tumors has largely remained unexplored. Herein, we investigated the association of HPV with aberrant methylation in tumor-related genes/loci consisting of the classical CpG Island Methylator Phenotype (CIMP) panel markers (p16, MLH1, MINT1, MINT2, and MINT31) and other frequently methylated cancer-related genes (DAPK1, GSTP1, BRCA1, ECAD, and RASSF1) and survival of UDAT cancers. The study includes 219 SCC of UADT patients from different hospitals of Northeast India.
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