Mini-Reviews in Organic Chemistry - Volume 19, Issue 1, 2022

The genus Flindersia comprises 17 species distributed in Australia, New Caledonia, New Guinea, and the Maluku Islands. With a variety of classes of secondary metabolites, including terpenes, alkaloids, lignans, flavonoids, coumarins, among other compounds, to date, the genus has not been widely studied phytochemically, having more value in the timber industry. However, the objective of this review is to gather the necessary information for future research on this genus, for the inclusion of new chemical constituents and biological activities. Thus, we show that the genus Flindersia has more than 160 isolated or identified compounds. In addition, the alkaloids in this genus confer antimalarial activity.

Diabetes mellitus refers to one of the leading cause of diseases that affect large populations of human and is characterized by a high glucose level in the blood (also known as hyperglycemia). Thiazolidinedione (TZD) is a five-member heterocyclic compound consisting of three carbons, nitrogen and sulfur. It is also known as glitazones, can be used as potent hypoglycemic agents and is also reduce many other cardiovascular risk factors including percutaneous coronary intervention, carotid and coronary atherosclerosis. As it plays a very important role in the field of medicinal chemistry or pharmaceutical sciences, novel medicine developed and many are on underdevelopment, these derivatives have thiazolidinedione as their primary nucleus. This article has discussed the different synthetic procedures of thiazolidinediones that exhibited potential antidiabetic activity by the activation of PPAR-γ, by reducing the blood glucose levels and by different metabolic process incorporation. Thiazolidinediones has effective profile as the future investigational drug and can be processed in drug discovery because of its efficient anti-diabetic potential.

Recent studies have shown that one-pot synthesis is a boon for triazines synthesis. One-pot processes had significant success in carrying out complex reactions under mild and eco-friendly conditions. One-pot synthesis is environmentally benign and more economical than other processes of triazine synthesis. The triazine scaffold has provided the starting key point for the design and development of pharmaceutical molecules with a wide range of biomedical applications. This review highlights the various methodologies involved for one-pot synthesis of 1,3,5-triazine scaffolds

The marine sponges of the genus Oceanapia sp. is comprised of more than 50 species and are distributed in the seas around the tropical and subtropical regions. They are mainly found in the northern Indian oceans, Japan, and the south pacific coast. They are highly colored and known to be a rich source of various secondary metabolites, particularly alkaloids. Several other secondary metabolites are also reported from this genus which include terpenes, sphingolipids, ceramides, cerebrosides, acetylenic acids, and thiocyanatins, etc. Many of these compounds isolated from this genus exhibited various biological properties, including anticancer, antimicrobial, anti-HIV, ichthyotoxicity, and nematocidal activities. Although several secondary metabolites have been reported from this genus, a dedicated review of the chemicals and biological activities of this genus is so far lacking. Keeping this in mind, this review describes the various chemical entities isolated from the sponges of the genus Oceanapia, providing details of their chemical structures along with their reported biological properties

This review describes the synthesis and chemical reactivity of tetrahydrothieno[3,2-b] quinoline derivatives through many reagents such as; 1, 2-dihydropyridine-3-carbonitrile; 1,6-dihydropyrimidine- 5-carbonitrile; 2,3-dihydropyridazine-4-carbonitrile; 3-amino-thiophene-2-carboxylate; 3- amino-thiophene-2-carbonitrile; 3,4-diaminothieno[2,3-b] thiophene-2,5-dicarbo- nitrile; 2-(3-bromo-1- iodoisoquinolin-8-yl) benzonitrile and 3-mercapto-benzo[g]quinolin-4(1H)-one derivatives. The synthesis of tetrahydrothieno [3, 2-b] quinoline derivatives was explained through the following chemical reactions: Aldol condensation, alkylation, cyclocondensation, dehydration, chlorination, Wolff-Kishner reduction, acylation, Friedlander reaction and intramolecular cyclization

Catalysts contribute significantly to the industrial revolution in terms of reaction rates and reduction in production costs. Extensive research has been documented on various industrial catalysis in the last few decades. The performance of catalysts is influenced by many parameters, including synthesis methods. The current work overviews the most common methods applied for the synthesis of supported catalysts. This review presents the detailed background, principles, and mechanism of each preparation method. The advantages and limitations of each method have also been elaborated in detail. In addition, the applications of each method in terms of catalyst synthesis have been documented in the present review paper.

Hydroxychloroquine (HCQ) is an extremely important drug used for the treatment of various ailments. WHO listed it as one of the essential drugs. The utility of hydroxychloroquine (HCQ) as prophylaxis of COVID19, although debated, is well known. We have reviewed synthetic strategies for the industrial and academic synthesis of HCQ and its key intermediates like 4,7-dichloroquinoline (4,7- DCQ) and 2-((4-aminopentyl)(ethyl)amino)ethan-1-ol 9 (aka hydroxy novaldiamine; HNDA). The review is expected to provide the right perspective of state-of-the-art knowledge in this field so that further developments are possible.

The review discusses different methods for the preparation of 2,6-diphenyl-piperidin-4-one derivatives. 2,6-Diphenyl-piperidin-4-one is prepared from aromatic aldehyde and acetone in ammonium acetate. Reaction of 1-phenylsulfinylpropan-2-one or 1-(4-chlorophenylsulfinyl)propan-2-one, aromatic aldehyde and ammonium acetate gives a series of 2,6-diaryl-2,3-dihydro-1H-pyridin-4-one 6a,b. 4-Phenyl-2-amino-1,3-butadienes reacts with N-allyl benzaldimine through Diels-Alder reaction to afford 2,6-diphenyl-4-piperidinone derivative 7. Also, reactions of 2,6-diphenyl-piperdin-4-one are discussed. The reactions of the latter compounds can be on nitrogen atom or carbonyl function group or methylene group adjacent to the carbonyl group. In addition, different applications of 2,6-diphenylpiperidin- 4-one are summarized.