DL-3-Aminoisobutyric acid hydrate

BACKGROUND AND AIMS: The depletion of the ozone layer allows overexposure of the skin to UV radiation, which is prolonged due to the increasing life expectancy, together with inappropriate life habits contribute to the increasing incidence of cutaneous malignancies. Plant extracts with antioxidant capacities are frequently employed as a means to protect skin against ultraviolet (UV) radiations, thus preventing skin cancers. In the present study we assessed a red grape seed extract (GSE) potential capacities to reduce ultraviolet B (UVB) radiation-induced reactive oxygen species (ROS) and subsequent apoptosis in a human keratinocytes cell line (HaCaT). We identified molecules and pathways modulated by the GSE through which this may exert its photoprotective effect.

The spore-forming obligate anaerobeClostridium difficileis a leading cause of antibiotic-associated diarrhea around the world. In order forC. difficileto cause infection, its metabolically dormant spores must germinate in the gut of susceptible hosts. During germination, spores degrade their protective cortex peptidoglycan layer, release dipicolinic acid (DPA), and hydrate their core. InC. difficile,cortex hydrolysis precedes DPA release, whereas inBacillus subtilisDPA release is necessary for cortex hydrolysis. Given this difference, we tested whether DPA synthesis and/or release was required forC. difficilespore germination by constructing mutations in eitherspoVACordpaAB, which respectively encode an ion channel predicted to transport DPA into the forespore and the enzyme complex predicted to synthesize DPA.C. difficile spoVACanddpaABmutant spores lacked DPA but could be stably purified and were more hydrated than wildtype spores; in contrast,B.

A one-pot reaction of 6-methyl-3-thioxo-3,4-dihydro-[1,2,4]triazin-5-one 1 with selected aldehydes 2a-d and chloroacetic acid afforded the respective 2-arylidene-6-methyl-thiazolo[3,2-b][1,2,4]triazine-3,7-diones 4a-d. Compunds 4a-d could be also obtained via the reaction of 1 with chloroacetic acid in refluxing acetic acid to give 6-methyl-thiazolo[3,2-b][1,2,4]triazine-3,7-dione 3 then, Knoevenagel condensation of 3 with aldehydes 2a-d gave compounds 4a-d. Heterocyclization of 4a-c with hydrazine hydrate and phenylhy- drazine gave the corresponding pyrazolines 5a-c and 6a-c, respectively. Moreover, 7-amino-9-(aryl)-3-methyl-2-oxo-2H-pyrido[2',3':4,5][1,3]thiazolo[3,2-b][1,2,4]triazine-8-carbonitrles 7a-c were synthesized by the reaction of 4a-c with malononitrile in the presence of ammonium acetate. The structures of newly synthesized compounds were confirmed by analytical and spectroscopic measurements. Some selected new compounds were screened for their cytotoxic activities against three human cancer cell lines (HepG2, MCF-7 and A549) using SRB assay and the structure-activity relationship (SAR) was discussed.

AIM: To investigate the effect and mechanism of stimulation of the hypothalamic paraventricular nucleus with glutamate acid in rats with ulcerative colitis (UC).