Dual responsive phase behavior of nonionic cellulose-based polymer brushes by visible-light-driven organocatalyzed atom transfer radical polymerization.

Hydroxypropyl cellulose (HPC) is a nonionic, thermo-responsive polymer with temperature-dependent phase behavior. This behavior can be modified by grafting molecular units and polymer brushes onto the cellulose backbone. However, the thermo-response of such modified celluloses under biological and environmental conditions, such as pH, has been scarcely reported.

Revolutionizing photocatalysis: Synthesis of innovative poly(N-tertiary-butylacrylamide)-graft-hydroxypropyl cellulose polymers for thermo-responsive applications via metal-free organic photoredox catalysis.

In this study, we present a groundbreaking approach utilizing metal-free, visible light-mediated organic photoredox catalyzed atom transfer radical polymerization (O-ATRP) to synthesize cellulose-based stimuli-responsive polymers. Our method resulted in the successful synthesis of innovative metal-free poly(N-tertiary-butylacrylamide)-graft-hydroxypropyl cellulose (PNTBAM-g-HPC) polymers with exceptional control over molecular weight and narrow dispersity index (Đ) and explored their applications in organo-photocatalytic reactions. This approach addresses the limitations of traditional atom transfer radical polymerization method, which suffer from metal contamination and toxicity related problems.

Designing efficient A-D-A-D-A type fullerene free acceptor molecules with enhanced power conversion efficiency for solar cell applications.

The achievement of highly efficient power conversion efficiency (PCE) is a big concern for non-fullerene organic solar cells (NF-OSCs) because PCE can depend on numerous variables. Here, new five novel acceptor molecules without fullerenes were developed and investigated using DFT (density functional theory) and TD-DFT (time dependent-density functional theory). Compared to the recently synthesized molecule (PZ-dIDTC6), the developed molecules display a narrow optical band gap, exhibiting a red shift in the absorption spectrum.

Base-Promoted One-Pot Synthesis of Pyridine Derivatives via Aromatic Alkyne Annulation Using Benzamides as Nitrogen Source.

In the presence of CsCO, the first simple, efficient, and one-pot procedure for the synthesis of 3,5-diaryl pyridines via a variety of aromatic terminal alkynes with benzamides as the nitrogen source in sulfolane is described. The formation of pyridine derivatives accompanies the outcome of 1,3-diaryl propenes, which are also useful intermediates in organic synthesis. Thus, pyridine ring results from a formal [2+2+1+1] cyclocondensation of three alkynes with benzamides, and one of the alkynes provides one carbon, whilst benzamides provide a nitrogen source only.

Biaryl Formation via Base-Promoted Direct Coupling Reactions of Arenes with Aryl Halides.

In the absence of ligand, CsCO-promoted cross-coupling reaction of arenes with cyano-/nitro-substituted aryl halides in DMSO affording biaryls is reported. The cyano/nitro group in biaryls is useful and convenient for further transformation. The formation of dibenzofurans resulting from the reactions between arenes and 1-bromo-2-iodobenzene is also reported.

Base-Promoted Annulation of Amidoximes with Alkynes: Simple Access to 2,4-Disubstituted Imidazoles.

An efficient construction of imidazole ring by a CsCO-promoted annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synthetic route with high atom-utilization for the synthesis of 2,4-disubstituted imidazoles in good yields under transition-metal-free and ligand-free conditions. Internal alkynes can also undergo the annulation to give 2,4,5-trisubstituted imidazoles.

Quinazolinone Synthesis through Base-Promoted SAr Reaction of -Fluorobenzamides with Amides Followed by Cyclization.

A transition-metal-free synthesis of quinazolin-4-ones by CsCO-promoted SAr reaction of -fluorobenzamides with amides followed by cyclization in dimethyl sulfoxide has been developed. The present procedure can provide efficient synthetic methods for the formation of both 2-substituted and 2,3-disubstituted quinazolin-4-one rings depending on the use of easily available starting materials and an efficient, one-pot protocol for the synthesis of the marketed drug product of methaqualone.

Congenital anomaly of coronary artery: absence of left circumflex artery.

The prevalence of congenital coronary artery anomalies is approximately 1% in the general population. They are a common cause of sudden death in younger persons. Congenital absence of the left circumflex artery is usually a benign condition but can cause symptoms of exertional angina.

A Rare Case of Cyclical Hemothorax: Thoracic Endometriosis Syndrome.

Endometriosis is a common condition in which endometrial cells and stroma are deposited in extrauterine sites. Its prevalence has been estimated to be 10% of reproductive age females. It is commonly found in the pelvis; however, it may be found in the abdomen, thorax, brain, or skin.

Microbial transformation of anti-cancer steroid exemestane and cytotoxicity of its metabolites against cancer cell lines.

Background: Microbial transformation of steroids has been extensively used for the synthesis of steroidal drugs, that often yield novel analogues, not easy to obtain by chemical synthesis. We report here fungal transformation of a synthetic steroidal drug, exemestane, used for the treatment of breast cancer and function through inhibition of aromatase enzyme.

Results: Microbial transformation of anti-cancer steroid, exemestane (1), was investigated by using two filamentous fungi.