Synthesis of Isatin-derived Heterocycles with Promising Anticancer Activities.

Isatin or 1H-indole-2,3-dione skeleton has been playing a significant role in drug de-sign and development. Isatin itself and many of its derivatives are widely distributed in naturally occurring bioactive compounds. Various synthetic isatin derivatives were found to possess a broad range of significant pharmacological efficacies especially anti-cancer activity against a wide variety of cancer cell lines.

Tetrabutylammonium Bromide (TBAB) Catalyzed Synthesis of Bioactive Heterocycles.

During the last two decades, tetrabutylammonium bromide (TBAB) has gained significant attention as an efficient metal-free homogeneous phase-transfer catalyst. A catalytic amount of TBAB is sufficient to catalyze various alkylation, oxidation, reduction, and esterification processes. It is also employed as an efficient co-catalyst for numerous coupling reactions.

Recent developments on ultrasound assisted catalyst-free organic synthesis.

Mother Nature needs to be protected from ever increasing chemical pollutions associated with synthetic organic processes. The fundamental challenge for today's methodologists is to make their protocols more environmentally benign and sustainable by avoiding the extensive use of hazardous reagents and solvents, harsh reaction conditions, and toxic metal catalysts. However, the people of the twenty-first century are well aware about the side effects of those hazardous substances used and generated by the chemical processes.

Recent developments on ultrasound-assisted one-pot multicomponent synthesis of biologically relevant heterocycles.

Heterocycles are the backbone of organic compounds. Specially, N- &O-containing heterocycles represent privileged structural subunits well distributed in naturally occurring compounds with immense biological activities. Multicomponent reactions (MCRs) are becoming valuable tool for synthesizing structurally diverse molecular entities.

Sunlight-induced rapid and efficient biogenic synthesis of silver nanoparticles using aqueous leaf extract of Linn. with enhanced antibacterial activity.

Background: Nanotechnology is now regarded as a distinct field of research in modern science and technology with multifaceted areas including biomedical applications. Among the various approaches currently available for the generation of metallic nanoparticles, biogenic synthesis is of increasing demand for the purpose of . Among various natural sources, plant materials are the most readily available template-directing matrix offering cost-effectiveness, eco-friendliness, and easy handling.

Crystal structure of 5,5'-[(4-fluoro-phen-yl)methyl-ene]bis-[6-amino-1,3-di-methyl-pyrimidine-2,4(1H,3H)-dione].

In the title mol-ecule, C19H21FN6O4, the dihedral angles between the benzene ring and essentially planar pyrimidine rings [maximum deviations of 0.036 (2) and 0.056 (2) Å] are 73.

6-Amino-3-methyl-4-(3,4,5-tri-meth-oxy-phen-yl)-2,4-di-hydro-pyrano[2,3-c]pyrazole-5-carbo-nitrile.

In the title compound, C17H18N4O4, the dihedral angle between the benzene ring and 2,4-di-hydro-pyrano[2,3-c]pyrazole ring system is 89.41 (7)°. The pyran moiety adopts a strongly flattened boat conformation.

Ethyl 6-amino-5-cyano-4-phenyl-2,4-di-hydro-pyrano[2,3-c]pyrazole-3-carboxyl-ate dimethyl sulfoxide monosolvate.

In the asymmetric unit of the title compound, C16H14N4O3·C2H6OS, there are two independent main mol-ecules (A and B) and two dimethyl sulfoxide solvent mol-ecules. In mol-ecule A, the pyran ring is in a flattened sofa conformation, with the sp (3)-hydridized C atom forming the flap. In mol-ecule B, the pyran ring is in a flattened boat conformation, with the sp (3)-hydridized C atom and the O atom deviating by 0.

Facile synthesis of symmetrical bis(benzhydryl)ethers using p-toluenesulfonyl chloride under solvent-free conditions.

Background: The benzhydryl ether moiety is widely distributed in nature and constitutes a key structural motif in numerous molecules of significant biological potential and of prospective clinical uses. Solvent-free and cost-effective facile synthesis of symmetrical bis(benzhydryl)ethers is, thus, much desirable.

Results: A simple and efficient method for the facile synthesis of symmetrical bis(benzhydryl)ethers directly from the corresponding benzhydrols has been developed using a catalytic amount of p-toluenesulfonyl chloride (5 mol%) at an oil bath temperature of 110°C under solvent-free conditions.

2-Amino-7,7-dimethyl-5-oxo-4-(p-tol-yl)-5,6,7,8-tetra-hydro-4H-chromene-3-carbonitrile.

In the title mol-ecule, C(19)H(20)N(2)O(2), the cyclo-hexene ring adopts a sofa conformation, while the pyran ring adopts a flattened boat conformation. In the crystal, mol-ecules are linked by N-H⋯N and N-H⋯O hydrogen bonds, forming a two-dimensional network parallel to (010).

Trimeth-yl(triphenyl-meth-oxy)silane.

In the title mol-ecule, C(22)H(24)OSi, the Si-O-C angle is 139.79 (11)°, the O-C-C angles of the triphenyl-meth-oxy group are in the range 106.13 (13)-109.