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The maximum quantum yield of photosystem II (as reflected by variable to maximum chlorophyll a fluorescence, Fv /Fm ) is regarded as one of the most important photosynthetic parameters. The genetic basis underlying natural variation in Fv /Fm , which shows low level of variations in plants under non-stress conditions, is not easy to be exploited using the conventional gene cloning approaches. Thus, in order to answer this question, we have followed another strategy: we used genome-wide association study (GWAS) and transgenic analysis in a rice mini-core collection. We report here that four single-nucleotide polymorphisms, located in the promoter region of β-glucosidase 5 (BGlu-5), are associated with observed variation in Fv /Fm . Indeed, our transgenic analysis showed a good correlation between BGlu-5 and Fv /Fm . Thus, our work demonstrates the feasibility of using GWAS to study natural variation in Fv /Fm , suggesting that cis-element polymorphism, affecting the BGlu-5 expression level, may, indirectly, contribute to Fv /Fm variation in rice through the gibberellin signaling pathway. Further research is needed to understand the mechanism of our novel observation.

Diabetes mellitus is one of the most prevalent diseases nowadays. Several marketed drugs are available for the cure and treatment of diabetes, but there is still a dire need of introducing compatible drug molecules with lesser side effects. The current study is based on the synthesis of isatin thiazole derivatives 4-30 via the Hantzsch reaction. The synthetic compounds were characterized using different spectroscopic techniques and evaluated for their α-amylase and α-glucosidase inhibition potential. Of 27 isatin thiazoles, five (4, 5, 10, 12, and 16) displayed good activities against the α-amylase enzyme with IC

Inflammation is common localized condition which makes body reddened and swollen due to some injury or any infection. The commonly available drugs i. e. diclofenac, ibuprofen etc. in market against inflammation bear acid group which cause severe stomach disturbance in their prolong use. Thus, such issues required significant attention in term of introducing acid free new anti-inflammatory agents with enhance efficacy. In the present study, we screened a series of eighteen aminoquinoline Schiff bases for their anti-inflammatory activity. These compounds were tested for their inhibitory effect on intracellular reactive oxygen species (ROS) produced from phagocytes isolated from human whole blood. Among the synthetic analogs, (E)-4-((quinolin-5-ylimino)methyl)benzene-1,2,3-triol (5), (E)-1-(2,4-dimethoxyphenyl)-N-(quinolin-5-yl)methanimine (6), (E)-2,6-dimethoxy-4-((quinolin-5-ylimino)methyl)phenol (7), and (E)-4-((quinolin-3-ylimino)methyl)benzene-1,2,3-triol (15) were found to exhibit potent activity with IC50 values of 1.9 ± 0.9, 2.7 ± 0.5, 1.4 ± 0.1, and 2.4 ± 0.1 μg/mL, respectively. Ibuprofen with IC50 value of 2.5 ± 0.6 μg/mL has been used standard in this assay. Cytotoxicity of these compounds was also tested against rat fibroblast cell line (3T3 cell line). The synthetic aminoquinoline Schiff bases were found to be non-toxic in cellular model except trihydroxy derivative 5. The active compounds can serve as potential leads for new anti-inflammatory drugs.

A new and facile CuCl2·2H2O-catalyzed one-pot three-component synthesis for quinazolines has been developed. A mixture of readily available 2-amino-5-chlorobenzophenones, substituted benzaldehydes, ammonium acetate, and CuCl2·2H2O in ethanol was refluxed altogether to afford the desired products in quantitative yields without any purification requirements. Structures of the products were confirmed by 1H NMR and EI-MS. A plausible reaction mechanism is also discussed.

A diverse range of benzoic and sulfonic acid derivatives including biologically and pharmaceutically relevant ones are efficiently transformed into acyl and sulfonyl hydrazines.

To evaluate the effect of substituents on biological activities of electron-rich N-containing heterocycles, the variably 2-substituted 5,6-dihydro-5-oxo-4H-1,3,4-oxadiazine-4-propanenitriles 26–33 were synthesized and evaluated for antibacterial, antifungal, and enzyme-inhibition activities. The target compounds were obtained from alkyl 4- or 3-hydroxy benzoates 1 and 2, respectively, and from methyl indoleacetate 3. The phenolic OH group of benzoates 1 and 2 were substituted with p-toluenesulfonyl (4 and 5), benzoyl (6 and 7), and benzyl groups (8 and 9) and then converted to 5,6-dihydro-5-oxo-4H-1,3,4-oxadiazine-4-propanenitriles. To establish structure-activity relationships (SAR), a pharmacological screening of the intervening intermediates was also conducted, which revealed that the intermediate hydrazide 11 possesses significant antimicrobial and MAO-A inhibiting properties and intermediates 12, 24, 28, and 29 appreciable antifungal activities. Compound 7 inhibits α-chymotrypsin.

A route to optically active variously substituted 4-methyl- and 4-methyl-7-substituted 1,3,4,5-tetrahydro-2H-1,5-benzo-diazepin-2-ones as analogues of commercially available Lofendazam (7-chloro-5-phenyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-2-one, 1) was developed. Fortyone variously substituted optically active compounds having the same configuration were prepared and the UV and CD spectra of the parent compounds bearing no additional substitution in the benzene ring are discussed.

The syntheses of 5α- and 5β-cholest-3-eno[4,3-d]pyrimidines (7) and (7′) could be achieved by using the hydroxymethylene derivative of cholestan-4-one (5) prepared from cholesterol (1). Their 2′-derivatives 7a-7d and 7′a-7′c were also synthesized. 5α-Cholest-6-eno[7,6-d]pyrimidine (13) was prepared by the reaction of 5α-cholestan-7-one (12) with tris-(formylamino)methane. The CD spectra exhibit at least three Cotton effects between 300 and 210 nm, a first CD band around 290, a second one around 260, and a third one around 220 nm. An earlier developed quadrant rule can be applied to the determination of the sign of the first CD band, while the suggested helicity rule allows prediction of the third CD band.

An eco-benign method for the synthesis of title compounds (III) is developed using NH4Cl in stoichiometric amount as enolization activator in water.

The title method is chemoselective and tolerates various functional groups such as hydroxyl and amino groups.

The syntheses of 5α- and 5β-cholest-3-eno[4,3-d]pyrimidines (7) and (7′) could be achieved by using the hydroxymethylene derivative of cholestan-4-one (5) prepared from cholesterol (1). Their 2′-derivatives 7a-7d and 7′a-7′c were also synthesized. 5α-Cholest-6-eno[7,6-d]pyrimidine (13) was prepared by the reaction of 5α-cholestan-7-one (12) with tris-(formylamino)methane. The CD spectra exhibit at least three Cotton effects between 300 and 210 nm, a first CD band around 290, a second one around 260, and a third one around 220 nm. An earlier developed quadrant rule can be applied to the determination of the sign of the first CD band, while the suggested helicity rule allows prediction of the third CD band.

A route to optically active variously substituted 4-methyl- and 4-methyl-7-substituted 1,3,4,5-tetrahydro-2H-1,5-benzo-diazepin-2-ones as analogues of commercially available Lofendazam (7-chloro-5-phenyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-2-one, 1) was developed. Fortyone variously substituted optically active compounds having the same configuration were prepared and the UV and CD spectra of the parent compounds bearing no additional substitution in the benzene ring are discussed.

From forty one chiral benzodiazepin-2-ones the UV and CD data are reported and the bands discussed with respect to corresponding electronic transitions respectively stereochemical features.

A new method for the elimination of hydrogen halides and p-toluenesulfonic acid from sugar moieties using sodium hydride (NaH) in hexamethylphosphoric triamide (HMPA) at room temperature is reported. NaH/HMPA has several advantages compared to NaH/DMF: elimination products are produced in high yields even from sterically hindered starting materials, and not only from halides, but also tosylates.

The isolation and structure elucidation of a novel dimeric alkaloid, griffithine, from the leafy shoots of Sophora griffithii Stock (Papilionaceae) is described. The alkaloid possesses a 12-membered ring system formed by the linking of C-10 and C-10′ of the alkaloid with the N-1 and N-1′ atoms, respectively. The structure was established on the basis of extensive 1D and 2D NMR studies. The relative stereochemistry at the chiral centres was determined by NOE difference experiments. 10-Oxosparteine was isolated for the first time from the leafy shoots of Sophora griffithii.

A new series of 4-(4'-chlorophenyl)-4-hydroxypiperidine derivatives (2-5), substituted at nitrogen, were synthesized and tested as potential analgesic compounds as well as evaluated for their effect on hypotensive activity. Results showed that all the derivatives exhibit significant analgesic activity in male Wistar rats at a dose of 50 mg/kg of body weight after intramuscular injection, when tested by thermal stimuli (tail flick test). Pethidine was used as reference drug. Compounds 2, 3 and 5 produced reduction in blood pressure in normotensive rat.