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Several (+)- and (-)-α-pinene derivatives were synthesized and evaluated for their antimicrobial activity toward Gram-positive bacteria Micrococcus luteus and Staphylococcus aureus, Gram-negative bacterium Escherichia coli, and the unicellular fungus Candida albicans using bioautographic assays. (+)-α-Pinene 1a showed modest activity against the test organisms, whereas (-)-α-pinene 1b showed no activity at the tested concentration. Of all the α-pinene derivatives evaluated, the β-lactam derivatives (10a and 10b) were the most antimicrobial. The increase in the antimicrobial activity of 10a compared to 1a ranged from nearly 3.5-fold (C. albicans) to 43-fold (S. aureus). The mean ± standard deviation for the zone of inhibition (mm) for 10a (C. albicans) was 31.9 ± 4.3 and that for S. aureus was 51.1 ± 2.9. Although (-)-α-pinene 1b was not active toward the test microorganisms, the corresponding β-lactam 10b, amino ester 13b, and amino alcohol 14b showed antimicrobial activity toward the test microorganisms. The increase in the antimicrobial activity of 10b compared to 1b ranged from 32-fold (S. aureus) to 73-fold (M. luteus). The mean ± standard deviation for the zone of inhibition (mm) for 10b (S. aureus) was 32.0 ± 0.60 and that for M. luteus was 73.2 ± 0.30.

Psoralea corylifolia (PC), a medicinal plant, is used in traditional medicine to treat diabetes. Purpose of the research was to examine the antidiabetic and antilipemic potential of PC and to determine the relationship between its antidiabetic potential and the trace elements present. Wistar rats (150–200 g) with fasting blood glucose (FBG) of 80–110 mg dl−1(sub-diabetic) and 150–200 mg dl−1(mild diabetic) were selected for the short term antidiabetic studies and severely diabetic rats (FBG > 300 mg dl−1) were chosen for the long term antidiabetic and hypolipemic studies of PC seed extract. Laser induced breakdown spectroscopy (LIBS) was used to detect trace elements in the PC extract and the intensity ratios of trace elements were estimated. The dose of 250 mg kg−1 of PC extract was found to be the most effective in lowering blood glucose level (BGL) of normal, sub, mild and severely diabetic rats during FBG and glucose tolerance test (GTT) studies. Lipid profile studies on severely diabetic rats showed substantial reduction in total cholesterol, triglycerides, very low density lipoprotein, and low density lipoprotein and an increase in the total protein, body weight, high density lipoprotein, and hemoglobin after 28 days of treatment. Significant reduction in urine sugar and protein levels was also observed. LIBS analysis of the PC extract revealed the presence of Mg, Si, Na, K, Ca, Zn and Cl. The study validates the traditional use of PC in the treatment of diabetes and confirms its antilipemic potential. The antidiabetic activity of PC extract may partly be due to the presence of appreciable amounts of insulin potentiating elements like Mg, Ca, and K.

Musca domestica L. is a non-biting nuisance fly that is capable of transmitting a large variety of pathogens to humans and non-human animals. Natural compounds and their derivatives, which are often less toxic than entirely synthetic compounds, may be used as repellents against M. domestica as part of comprehensive pest control and disease mitigation programs. This work investigates the repellent properties of the natural compound α-pinene against M. domestica. Adult house flies of both sexes avoided the volatile plant-derived terpenes (1S)-(-)-α-pinene 1 and (1R)-(+)-α-pinene 2 in constant air flow laboratory conditions, with 1 exhibiting a stronger repellent effect. House flies also avoided tarsal contact with filter paper saturated with 1. Furthermore, both 1 and 2 are electrophysiologically active on in situ female house fly antennal preparations. These findings demonstrate that α-pinene exhibits natural baseline repellency against the house fly, elicits a specific physiological response in this fly, and that functional or structural modification of 1 in particular may yield novel fly repellents with desirable properties.

α-Pinene, a rigid bicyclic monoterpene, was altered by functional group transformations and the antimicrobial activity of the resulting compounds was studied using thin layer chromatography-autobiographic assay to determine the effect of structure on antimicrobial activity. Except for α-pinanone (and α-pinene oxide in two cases), all oxygenated α-pinene derivatives showed greater antimicrobial activity against Escherichia coli, Staphylococcus aureus, Micrococcus luteus and Candida albicans than α-pinene. Conformationally flexible methyl cyclohexene and some of its oxygenated derivatives were also tested to evaluate the role of carbon skeleton in determining the antimicrobial activity. The results indicate that both functional groups and carbon skeleton affect the antimicrobial activity of the compound and adding nitrogen to the carbon framework increases the antimicrobial activity. The results also confirm that introduction of oxygen function to the carbon framework increases antimicrobial activity.

The diazirine 1, upon thermolysis or photolysis in either acetone or cyclohexanone, at different concentrations, yield the spiro epoxides 2 and 3, and 4 and 5, respectively (Scheme 1). Yield of 2 and 3 depended both on the temperature and the concentration, and correlated inversely with the yield of the major by-product, the enol-derived glycoside 6. Other by-product were the benzyloxglycal7 and the lactone azines 8. ZnCl2-Promoted methanolysis of 2 under mild condition yielded mixture of the uloside 9 and 10 (1.2:1); similarly, 4 yielded 11 and 12 (1.8:1; Scheme 2). More strongly acidic conditions converted 11 into 12, evidencing that ZnCl2-promoted methanolysis proceeds under kinetic control, which is rationalized. The diazirine 13, upon thermolysis of Photolysis in either acetone of cyclohexanone, yielded the α-D-configurated spiro epoxides 14 and 16, and the α-D-configurated dihydrooxazoles 15 and 17, respectively (Scheme 3), which are either formed by ring-opening of s-D-epoxides, by competitive interception of the initially formed, hypothetical addition products of the intermediate carbene to the ketones. The glycosylidene carbenes, derived from 1 or 13 are not very reactive towards ketones, yields are good only when sterically unhindered ketones are used in large excess.

Piperidinium tetrathiotungstate has been found to react with a number of 1,n-dihalo compounds to afford the corresponding cyclic disulfides in good yields, under mild reaction conditions. This new methodology has been used as a key step in the synthesis of (+/-)-lipoic acid (35) and asparagusic acid (37).

The diazirine 1, upon thermolysis or photolysis in either acetone or cyclohexanone, at different concentrations, yield the spiro epoxides 2 and 3, and 4 and 5, respectively (Scheme 1). Yield of 2 and 3 depended both on the temperature and the concentration, and correlated inversely with the yield of the major by-product, the enol-derived glycoside 6. Other by-product were the benzyloxglycal7 and the lactone azines 8. ZnCl2-Promoted methanolysis of 2 under mild condition yielded mixture of the uloside 9 and 10 (1.2:1); similarly, 4 yielded 11 and 12 (1.8:1; Scheme 2). More strongly acidic conditions converted 11 into 12, evidencing that ZnCl2-promoted methanolysis proceeds under kinetic control, which is rationalized. The diazirine 13, upon thermolysis of Photolysis in either acetone of cyclohexanone, yielded the α-D-configurated spiro epoxides 14 and 16, and the α-D-configurated dihydrooxazoles 15 and 17, respectively (Scheme 3), which are either formed by ring-opening of s-D-epoxides, by competitive interception of the initially formed, hypothetical addition products of the intermediate carbene to the ketones. The glycosylidene carbenes, derived from 1 or 13 are not very reactive towards ketones, yields are good only when sterically unhindered ketones are used in large excess.

Piperidinium tetrathiotungstate has been found to react with a number of 1,n-dihalo compounds to afford the corresponding cyclic disulfides in good yields, under mild reaction conditions. This new methodology has been used as a key step in the synthesis of (+/-)-lipoic acid (35) and asparagusic acid (37).

Procedures to assess tobacco smoke exposure are reviewed and biomarkers used for determining the smoking status of an individual are compared. Methods used to extract these biomarkers from saliva, urine, and blood and the advantages and disadvantages of the assays are discussed. Finally, the procedures used to measure the levels of cortisol, a stress hormone speculated to be linked to nicotine metabolism, are discussed.

In an unusually novel reaction, piperidinium tetrathiotungstate has been found to induce reductive dimerization of a variety of sulfonyl derivatives to the corresponding disulfides under very mild conditions