Palladium(0) catalyzed Suzuki cross-coupling reaction of 2,5-dibromo-3-methylthiophene: selectivity, characterization, DFT studies and their biological evaluations

Abstract

Thiophene derivatives have shown versatile pharmacological activities. The Suzuki reaction proved a convenient method for C–C bond formations in organic molecules. In the present research work novel derivatives of 2,5-dibromo-3-methylthiophene (3a–k and 3l–p) has been synthesized, via Suzuki coupling reaction in low to moderate yields. A wide range of functional groups were well tolerated in reaction. Density functional theory investigations on all synthesized derivatives (3a–3p) were performed in order to explore the structural properties. The pharmaceutical potential of synthesized compounds was investigated through various bioassays (antioxidant, antibacterial, antiurease activities). The compounds 3l, 3g, 3j, showed excellent antioxidant activity (86.0, 82.0, 81.3%), respectively by scavenging DPPH. Synthesized compounds showed promising antibacterial activity against tested strains. 3b, 3k, 3a, 3d and 3j showed potential antiurease activity with 67.7, 64.2, 58.8, 54.7 and 52.1% inhibition at 50 µg/ml. Results indicated that synthesized molecules could be a potential source of pharmaceutical agents.Electronic supplementary materialThe online version of this article (10.1186/s13065-018-0404-7) contains supplementary material, which is available to authorized users.

Chemical composition, antioxidant and antimicrobial potential of essential oils from different parts of Daphne mucronata Royle

“…The antioxidant propensity of plant essential oils was checked by measuring their ability to scavenge stable DPPH free radical following the standard protocol as reported earlier by Rizwan and co-workers [24] with slight modifications. The 1 mL of 90 μM DPPH solution was mixed with the samples (from 10 to 500 μg mL −1 ) and 95% methanol was used to made the final volume up to 4 mL.…”

Palladium(0) Catalyzed Synthesis of (E)-4-Bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline Derivatives via Suzuki Cross-Coupling Reaction: An Exploration of Their Non-Linear Optical Properties, Reactivity and Structural Features

“…Lack of reactivity was observed with ortho -substituted arylboronic acids due to steric factors which hinder the in mechanism during the transmetalation step [ 21 , 22 ], and as a result low yields are obtained as in the cases of 5c and 5d ( Figure 1 ). When 3b was reacted with 2 equivalents of boronic acid, a double Suzuki coupling occurred and disubstituted products 6a – 6d were obtained in moderate yields (31–46%) ( Figure 1 ).…”

Facile synthesis of N- (4-bromophenyl)-1- (3-bromothiophen-2-yl)methanimine derivatives via Suzuki cross-coupling reaction: their characterization and DFT studies

“…Molecular electrostatic potential analysis by using computational methods is famous parameter to describe the distribution of charges and electronic density in newly synthesized compounds [ 15 – 17 ]. MEP analysis of compounds ( 3a – 3i ) was performed by using B3LYP/6-31G(d,p) method.…”