Classical and advanced chemical sciences
An efficient protocol for the synthesis of phenols from arylboronic acids has been developed by using t-butyl hydroperoxide (TBHP) as oxidant in water-ethanol as a binary reaction medium. The reaction is metal and additive free and does not require strong basic conditions. The developed protocol has a broad substrate scope and functional group compatibility. Notably the mild conditions, shorter reaction time, good to excellent yields and eco-friendly reaction medium are some important features of the developed method.
Keywords: arylboronic acids; tert-butyl hydroperoxide (TBPH); phenols; green method
One-pot three component synthesis of (Z)-N-5-(benzylidene/substituted benzylidene)-3-methyl-6-oxo-1,2,5,6-tetrahydro-1,2,4-triazine-2-substituted benzamide derivatives were described by one-pot reaction of (Z)-4-(benzylidene/ substituted benzylidene)-2-methyl-oxazol-5(4H)-ones with hydrazine hydrate followed by PhCH=NPh in [BMIM][OH] as ionic liquid for 30 min at 80-85 oC. The importance of this method includes shorter reaction time and high yield.
Keywords: One-pot synthesis, Schiff bases, [BMIM][OH], 1, 2, 4-triazine
Eco-friendly synthesis of (Z)-3-alkyl-5-(benzylidene/substituted benzylidene)- 2N-(carbothioamido)-6-oxo-1,2,5,6-tetrahydro-1-NH-1,2,4-triazine derivatives have been developed in 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as solvent without catalyst for 20-30 min at 60-65 oC with good yields.
Keywords:Eco-friendly synthesis; 1,2,4-triazines; 1,8-diazabicyclo[5.4.0]undec-7-ene
Chemical and biological aspects of life
Solanaceae is one of the most studied among all plant families. Plants of this family are very rich with medicinally active natural products, some of them, with nutritional importance. Some of these compounds are psychoactive and mind altering. Alkaloids, physalins and withanolides are the major notable active natural products present in these plants. In this review article, we will present the vast majority of published research about these plants. This work will include biological and medicinal activities, extended presentation of natural products, their activities and in some cases, their synthesis, biosynthesis and production, along with other chemical aspects. Despite all the wideness of this article, we have introduced limited (but not ignored. presentations of two important aspects of this plant family, mainly due to the large size of this article. One, ethnobotany and ethnomedicine uses of these plants, and two, the influence of various cultivation conditions on these plants, and the results of these conditions.
Keywords: Solanaceae; alkaloids; physalins; withanolides; medicinal activity; psychoactive; poisoning
The novel corona virus-2 (n-CoV-2) identified in the December 2019 which then spread worldwide has become pandemic in the form of Corona virus disease 2019 (COVID-19) and affected the health, economy and the medical system to a significant extent. As on date, around 8.20 million confirmed cases including death of around 443,815 have been reported. The present review deals with the history and origin of the COVID-19, its worldwide pandemic spread, symptoms and preventive measures as an attempt to create awareness of the fatal disease.
Keywords: COVID-19; global pandemic; corona; virus
Theoretical and computational chemistry
Abraham model L solute descriptors have been determined for 174 additional mono-methyl branched alkanes based on published linear-programmed gas chromatographic retention indices. Standard molar enthalpies of vaporization and sublimation at 298 K are calculated for the 174 mono-methylated alkanes using the reported solute descriptors and our recently published Abraham model correlations. Calculated vaporization and sublimation enthalpies derived from the Abraham model compare very favourably with values based on a popular atom-group additivity model. Unlike the additivity model the Abraham model gives different predicted values for each mono-methyl alkane having a given CnH2n+2 molecular formula.
Keywords: Chromatographic retention indices; Abraham model; solute descriptors; enthalpy of vaporization; enthalpy of sublimation