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Abstract: Melia azedarach L., a species of the mahogany family (Meliaceae), has long been used as a folk medicine for various diseases. Recent studies on this plant revealed that this plant contains many interesting bioactivities such as antioxidant, antimicrobial, antiviral, antifeedant, antidiabetic, antifungal, and cytotoxic activities. A diverse range of organic compounds has been isolated from this species, such as triterpenoids, limonoids, degraded limonoids, steroids, lignans, flavonoids, and phenolics. This review article will give a comprehensive overview of the chemical constituents and biological activity of Melia azedarach.

Background: An efficient and green strategy for the synthesis of 2-arylbenzoxazoles using [Bmim]PF6 ionic liquid as a catalyst has been investigated via the condensation of oaminophenol with aldehydes. The microwave-assisted synthesis features some advantages such as good yield of products, broad substrate scope, short reaction time, and absence of metal catalyst and solvent. Furthermore, the synthesis could be conveniently expanded to a gram scale. Methods: 2-arylbenzoxazoles were obtained from o-aminophenol with aldehydes using [Bmim]PF6 ionic liquid as a catalyst under microwave irradiation at 80ºC, 120 W. Results: Twenty-three 2-arylbenzoxazole derivatives were furnished in good to excellent yields under optimized conditions. The structures of these compounds were confirmed by analysis of NMR data. In addition, the method could be conveniently expanded to gram scale. Conclusion: An efficient and straightforward protocol for the synthesis of 2-arylbenzoxazoles catalyzed by [Bmim]PF6 ionic liquid has been demonstrated. The synthesis delivers several advantages such as short reaction time, broad substrate scope, scalability, solvent-free conditions, and high efficiency. The reaction mechanism and applications of this synthesis are currently ongoing in our lab and will be reported in due course.

Background: Thiazole-containing compounds are widely found in natural products as well as synthetic sources. Many thiazole-based compounds possess a broad spectrum of bioactivities, and some of them are well-known drugs in the markets. The use of thiazole derivatives in other fields such as organic materials, cosmetics, and organic synthesis has also been widely reported. Due to a wide range of applicability, the synthesis of thiazole-containing compounds has attracted extensive interest from chemists, and many studies in the synthesis of thiazole skeleton have been reported recently. Objective: This review article will discuss recent studies in the synthesis of thiazoles (from 2012). Besides the well-established Hantzsch thiazole synthesis, a large number of novel methods have been developed for the synthesis of thiazole derivatives. In most cases, reaction mechanisms have also been described. Conclusion: The synthesis of thiazole derivatives has drawn great attention from chemists, and many studies in the synthesis of these heterocycles have been reported recently. The classical method, the Hantzsch thiazole synthesis has received great research interest from chemists. Moreover, many new methods have been established to synthesize thiazole-derived compounds. Unquestionably, more and more approaches to access thiazole skeleton will appear in the literature. The application of well-established thiazole synthesis methods to the synthesis of drugs, organic materials, and natural products will almost certainly be studied.

Abstract: Limonoids are the most representative metabolites present in the order Rutales, which includes the families Rutaceae, Meliaceae and Cneoraceae. They are tetranortriterpenoids with a 4,4,8-trimethyl-17-furanylsteroidal skeleton, containing several oxygenated functions. The Meliaceae family consists of 50 genera with more than 1400 species distributed in tropical and subtropical regions worldwide. Plants of this family are found to be rich in limonoids. Limonoids from Meliaceae family exhibit a diverse range of bioactivities cytotoxic, antioxidant, anti-inflammatory, antimicrobial, antimalarial, and antifeedant, activities and some of them have been commercially used for different purposes. Numerous studies on limonoids from Meliaceae family and their bioactivities have been reported recently. This review covers the isolation and structure determination of limonoids reported during 2012–2022. 1172 novel limonoids in 118 papers have been summarized. Furthermore, important biological activities of these limonoids have also been outlined. This review can provide useful information for medicinal and pesticidal chemistry and phytochemistry researchers who are interested in the chemistry and biology of limonoids.

Abstact: An efficient and green method for the Friedländer quinoline synthesis has been described. The synthesis was performed under microwave irradiation using ionic liquid [Bmim]HSO4 as a catalyst. A diverse range of quinoline derivatives was obtained in high yields from 2-aminoaryl aldehydes and ketones under solvent-free conditions.

Abstract: Lamellarin alkaloid is a large class of marine alkaloids with diverse bioactivities. These heterocycles have been isolated from diverse marine organisms, mainly ascidians and sponges. They possess a fused 14-phenyl-6H-[1]benzopyrano[40,30:4,5] pyrrolo[2,1- a]isoquinoline or non-fused 3,4-diarylpyrrole-2-carboxylate ring systems. Until now, more than 50 lamellarins have been isolated from marine organisms. Various lamellarins exhibit valuable bioactivities, such as cytotoxicity, topoisomerase I inhibition, protein kinases inhibition, multidrug resistance reversal, and anti-HIV-1 activity. Due to their valuable biological activity, the synthesis of lamerallins has received great attention of chemists and a vast number of synthetic methods have been developed. This article gives overview of studies on lamellarins isolation, their bioactivities, and synthetic approaches for their total synthesis.

Supplemental material, sj-docx-1-npx-10.1177_1934578X231167229 for Phytochemical Analysis of the Essential Oils From the Rhizomes of Three Vietnamese Curcuma Species and Their Antimicrobial Activity by Hieu Tran-Trung, Xuan Duc Dau, Thi Chung Nguyen, Hien Nguyen-Thi-Thu, Hieu Nguyen-Ngoc, Thi Giang An Nguyen, Van Trung Hoang, Dang-Khoa Nguyen, Danh Duc Nguyen, Chen Tran Van and Le Duc Giang in Natural Product Communications

Procyanidin B1 is one of the natural dimeric flavonoids. It has established a great role in antioxidative activity. In the current study, we wish to provide crucial information on its antioxidative action by the DFT computational and docking approaches. From point of thermodynamic view, at the M062X/6-311G(d,p) level, the HAT (hydrogen atom transfer) and SPL-ET (sequential proton loss-electron transfer) are principal antioxidative routes of this compound in gas and methanol, respectively. OH groups of two phenyl rings of this molecule are likely to be the best antiradical sites. In the kinetics of the interactions with HOO