Reactive Oxygen Species (ROS): Key Components in Cancer Therapies.

Reactive Oxygen Species (ROS) refers to the highly reactive substances which contain oxygen radicals. Hypochlorous acid, peroxides, superoxide, singlet oxygen, alpha-oxygen, and hydroxyl radicals are the major examples of ROS. Generally, the reduction of oxygen (O2) in molecular form produces superoxide (•O2 -) anion.

Drug Repurposing Strategy (DRS): Emerging Approach to Identify Potential Therapeutics for Treatment of Novel Coronavirus Infection.

Drug repurposing is also termed as drug repositioning or therapeutic switching. This method is applied to identify the novel therapeutic agents from the existing FDA approved clinically used drug molecules. It is considered as an efficient approach to develop drug candidates with new pharmacological activities or therapeutic properties.

Green Synthetic Approach: An Efficient Eco-Friendly Tool for Synthesis of Biologically Active Oxadiazole Derivatives.

Green synthetic protocol refers to the development of processes for the sustainable production of chemicals and materials. For the synthesis of various biologically active compounds, energy-efficient and environmentally benign processes are applied, such as microwave irradiation technology, ultrasound-mediated synthesis, photo-catalysis (ultraviolet, visible and infrared irradiation), molecular sieving, grinding and milling techniques, etc. Thesemethods are considered sustainable technology and become valuable green protocol to synthesize new drug molecules as theyprovidenumerous benefits over conventional synthetic methods.

Microwave-Induced Ugi-Four Component Reactions: Synthesis of New Hetero- Steroid-Amino Acid Conjugates.

Background: Aza-steroids are an important class of compounds because of their numerous biological activities. The hetero steroids have different hydrogen bonding ability and hydrophobicity in comparison to steroids.

Materials And Methods: Microwave-induced synthesis of a novel type of hybrid hetero-steroid amine conjugates, following Ugi-four component reactions of steroidal amines with alanine and valine methyl esters as amino acid residues is described.

Polyaromatic Hydrocarbons (PAHs): Structures, Synthesis and their Biological Profile.

Polycyclic aromatic hydrocarbons (PAHs) are aromatic compounds with two or more fused benzene rings in their structural configurations. PAHs do not contain heteroatoms and substituents on the ring system. PAHs containing up to four rings are called light PAHs while those that contain more than four rings are considered as heavy PAHs.

An Overview on Steroids and Microwave Energy in Multi-Component Reactions towards the Synthesis of Novel Hybrid Molecules.

In recent years, hybrid systems are gaining considerable attention owing to their various biological applications in drug development. Generally, hybrid molecules are constructed from different molecular entities to generate a new functional molecule with improved biological activities. There already exist a large number of naturally occurring hybrid molecules based on both non-steroid and steroid frameworks synthesized by nature through mixed biosynthetic pathways such as, a) integration of the different biosynthetic pathways or b) Carbon- Carbon bond formation between different components derived through different biosynthetic pathways.

Cp*Co(iii)-catalyzed ortho-amidation of azobenzenes with dioxazolones.

Cp*Co(iii)-catalyzed C-H amidation of azobenzene with dioxazolones has been developed. The amidation reaction does not require external oxidants and gives carbon dioxide as the only by-product. Both symmetrical and unsymmetrical azobenzenes were found to undergo amidation smoothly with broad functional group tolerance.

Microwave (MW) promoted high yield expedient synthesis of steryl ferulates--A class of novel biologically active compounds: A comparative study of their antioxidant activity with that of naturally occurring γ-oryzanol.

Synthetic steryl ferulates [3-O-(trans-4-feruloyl)-sterols] are currently gaining considerable importance in recent years to be used as nutraceuticals and food additives as well as in pharmaceutical applications substituting γ-oryzanol - a class of naturally occurring steryl ferulates having potent antioxidant and other organoleptic properties. Considering the importance of this class of compounds coupled with green technology associated with microwave energy (MW) in organic synthesis, we report here an expedited and high yield synthesis of steryl ferulates from abundant steroids, viz., cholesterol, cholestanol, stigmasterol, stigmastanol, β-sitosterol, β-campesterol, β-campestanol and ergosterol applying MW energy in the crucial step of esterification process of sterols with trans-4-O-acetylferulic acid to furnish their esterified products, viz.

Microwave (MW) irradiated Ugi four-component reaction (Ugi-4CR): Expedited synthesis of steroid-amino acid conjugates--A novel class of hybrid compounds.

Microwave (MW) assisted chemical reactions are currently gaining considerable importance in organic synthesis to contribute in green technology. Considering the importance of peptidomimetic steroid-amino acid conjugates - a novel class of hybrid compounds having diverse biological properties, we report here synthesis of these compounds of alanine and valine methyl esters with seco-steroids (A, B and D ring cleavage) in expedited way by MW promoted Ugi-four-component reaction (Ugi-4CR).