Mechanistic studies of the reactions of some allylic halides

Imperial Users onl

Regioselective synthesis of new 2-(E)-cyano(oxazolidin-2-ylidene)thiazoles

Reaction of 2-(oxazolidin-2-ylidene)malononitrile (1) with phosphorus pentasulfide gave the corresponding thioamide derivative (2a) in a regioselective manner. Reaction of this compound with several α-bromocarbonyl compounds gave new 2-(E)-cyano(oxazolidin-2-ylidene)thiazoles (3a-g). The chemical structures of novel compounds were confirmed by 1H NMR, elemental analysis, FT-IR spectrometry and mass spectrophotometric analyses

PERIODONTITIS AND BIRTH OF PRETERM INFANTS WITH LOW WEIGHT: A REVIEW ARTICLE

Abstract. About 9.6% of infants are born prematurely around the world. In addition to infection of reproductive system, inflammation and infection of distant organs are one of the risk factors for preterm low birth weight (PTLBW). Since periodontitis is a prevalent disease and also premature labor is a common complication with high treatment cost, it is important to elucidate the relationship between these two conditions. Such a knowledge could be helpful to prioritize the preventive interventions for reduction of adverse pregnancy outcome. Epidemiologic studies , as the first line of evidence,showed the higher prevalence of PTLBW among women with periodontitis. When a condition is being proposed as a risk factor, it is necessary to explain the biologic mechanisms underlying such a relationship. The relationship between periodontitis and PTLBW is biologically plausible. Periodontitis is a chronic inflammatory disease in which anaerobic bacteria being colonized in deep pathologic pockets and produce large amount of inflammatory mediators. Perio-pathogens and their products enter the placenta and amniotic fluids. They could activate the inflammatory signaling pathways and induce the PTLBW. Despite the large number of randomized control trial (RCT) studies, the effect of periodontal treatmenton the incidence of PTLBW is not well understood. Although the periodontal treatment could not necessarily reduce the incidence of PTLBW, but oral hygiene, is a pivotal compartment of health care during pregnancy. The aim of this article was to review the current evidences about different aspects of the relationship between periodontitis and PTLBW.Key words: periodontitis, periodontal diseases, pregnancy, preterm birth, low birth weight

Synthesis and Investigation of Anti-Bacterial Effects of 2-amino-5-Nitrothiophene Derivatives

Introduction: The increasing drug resistance of bacteria against different antibiotics is a cause of development of antimicrobial compounds. The aim of this study was to investigate the synthesis and evaluation of antibacterial effects of 2-amino-5-nitrothiophene derivatives against Staphylococcus aureus and Escherichia coli. Strains.   Materials & Methods: As the first stage, 2-amino-5-nitro-thiophene derivatives were synthesized. The structures of the synthesized compounds were confirmed by means of IR, 1H NMR and 13C NMR measurements. In the second phase, these compounds were evaluated for antimicrobial effects by Agar Well Diffusion Method against Staphylococcus aureus and Escherichia coli. Strains. Then, the minimum inhibitory concentration (MIC) of these compounds were evaluated.   Findings: According to our finds, reaction of malononitrile, aryl isothiocyanate and bromonitromethane in the presence of sodium ethoxide in ethanol led to preparation of compounds 4a-e. The antibacterial effects showed that all the compounds had inhibitory effects against Staphylococcus aureus.   Discussion & Conclusion: Our investigation concluded that the structure-activity relationship (SAR) results indicated that the compound 4a showed a potent antibacterial activity against Staphylococcus aureus, while this combination proved no effects on Escherichia coli. 4c and 4d compounds demonstrated an inhibitory effect on Escherichia coli strain, while the compounds 4b and 4e indicated similar effects on both the bacteria (Staphylococcus aureus and Escherichia coli). Meanwhile, efficacy of the compounds4b and 4e against Staphylococcus aureus and Escherichia coli was the same. &nbsp

Chemical and Antimicrobial Studies of Cupressus sempervirens L. and C. horizentalis Mill. Essential Oils: Chemical and Antimicrobial Studies of Cupressus sempervirens L. and C. horizentalis

The essential oils of fresh fruits and terminal branches with adherent leaves of Cupressus sempervirens L. and C. horizentalis Mill., growing in Iran, were analyzedby gas chromatography-mass spectroscopy. The oils were also screened for bacteriostatic and fungistatic activities. Thirteen and ten components were identifiedin the essential oils of C. sempervirens and C. horizentalis, respectively. The main constituents of both fruits and leaves of C. sempervirens were a-pinene and Δ-3-carene, while they were α-pinene and Δ-2-carene for C. horizentalis. The essential oil of C. horizentalis leaves showed no antimicrobial activity against, Bacillussubtilis, Candida albicans, Escherichia coli and Staphylococcus aureus, while the essential oil of its fruits exhibited a weak effect on Bacillus subtilis. The essentialoil of C. sempervirens leaves and fruits showed stronger antimicrobial activity against tested microorganisms compared to C. horizentalis essential oils. C. sempervirens fruits were relatively rich in tannins, and the leaves and fruits of C. horizentalis were quite rich in saponins and tannins. The amounts of flavonoids and alkaloids were not very high in both parts of these plants

Regioselective Synthesis of New 2-(E)-Cyano(thiazolidin-2ylidene)thiazoles

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