Synthesis of Aryl Tetralone Derivatives by Chalcone Route

Podophyllotoxin is a potent antimitotic agent. Podophyllin is a resinous extract of medicinal plants Podophyllum emodi and Podophyllum peltatum belonging to the family Berbideraceae in which the podophyllotoxin is one of the main constituent. The toxicity of podophyllotoxin liberates as diarrhea, nausea, vomiting. Hence modifications in podophyllotoxin structure are required to reduce its toxicity and to enhance its biological activity. The biologically active and lesscytotoxic new tetralone intermediates of podophyllotoxin have been synthesized. The modification of podophyllotoxin structure might enhance the biological activity with favorable solubility and reduced toxicity. Some synthesized analogues of podophyllotoxin showed better antibacterial activity. The structures of the synthesized new tetralone compounds were confirmed by IR, 1H-NMR, 13C-NMR and Mass spectral data. They will be screened for biological activities.

It was planned to synthesize analogues of podophyllotoxin by modifying lactone ring-A with some linked to ring A is replaced by dimethoxy, methoxy, methyl, H. Chalcones 3a-d were prepared by Claisen-Schmidt reaction of acetophenone 1a-dwith 3, 4, 5-trimethoxybenzaldehyde separately in the presence of potassiumhydroxide in water-ethanol mixture. Cyclopropyl ketones 4a-d was prepared in good yields by the reaction of chalcones 2a-d with diiodomethane in presence of Zn-Cu couple.

Combination of ESI and MALDI-MS Imaging Enhances Analysis on Brain Gangliosides

Recent advances in matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging (MSI) have led to the direct analysis of tissue slices. The major advantage of MSI is its capability of simultaneously localizing and identifying a parent molecule and its metabolites without any labeling or any prior knowledge. MSI has beenextensively employed to detect the differentiated pattern of lipids in variousorgans in different diseases, such as brains in Alzheimer’s disease. Poor reproducibility of MALDI MSI analysis due to the heterogeneity of the matrix-analyte crystals, hinders its use on quantitative analysis. In addition, discontinuous ion flow due to quickly consumption of the samples under laser irradiation on specific site affects its ability in qualitative analysis. Although electrospray ionization mass spectrometry (ESI-MS) cannot directly be used for imaging, ESI tandem mass spectrometry (LC/ESI-MS/MS) can separate and distinguish gangliosides.

Zhang et al. have presented a promising workflow for qualitative, semi-quantitative and in situ analysis ofgangliosides by combining the MALDI MSI and ESI-MS. Following obtaining the brain from the mice, fresh-frozen murine brain sections were prepared and coated with matrix for subsequent MALDI MSI analysis. On the other hand, lipid was extracted from brain tissue by Bligh and Dyer method. The gangliosides extracts were re-suspended in water for ESI-MS analysis.

Diurnal Variations of Endogenous Steroids in the Follicular Phase of the Menstrual Cycle

Many studies have been conducted assessing biological changes in patients with both somatic and psychiatric conditions. Most studies of posttraumatic stress disorder (PTSD) have focused on the primary stress pathway: the hypothalamus-pituitary-adrenal axis (HPA), which is activated during acute stress. The hypothalamus secretes corticotropin-releasing factor (CRF) whichstimulates the pituitary to release adrenocorticotropic hormone (ACTH), resulting in the production of glucocorticoids and other steroids in the adrenal cortex. It is known that the secretion of cortisol is associated with the natural circadian rhythm, and the assessment of cortisol concentrations should be adjusted for the diurnal variation, with peak values in the morning just after awakening. As cortisol is one of the end products of the glucocorticoid biosynthesis pathway, it can be assumed that the biosynthesis of glucocorticoids upstream and other steroids also are affected by diurnal variations.

Dehydroepiandosterone (DHEA) and its sulfate (DHEAS) are synthesized from cholesterol, via pregnenolone (sulfate) and 17-hydroxypregnenolone, almost exclusively by theadrenals, only ± 10% of plasma DHEA is derived from the gonads. DHEAS is quantitatively the major steroid hormone secreted by the adrenals, and its plasma concentration in young adults is 10 to 20 times the cortisol concentration.

Adding Value to Agro-Industrial Wastes

Biomass refers to renewable organic materials, including agricultural products and agricultural wastes, wood and its wastes, animal wastes, urban wastes, aquatic plants, and so on. Lignocellulosic materials are the most abundant renewableorganic biomass on Earth, being constantly generated through photosynthesis and existing in large numbers and wide variety from the forest to the sea. This biomass is emerging as an energy source among many kinds of new energy including wind energy, hydroenergy, solar energy, nuclear energy, etc.

The use of biomass instead of coal and oil to produce chemical substances that satisfy human requirements has begun to be gradually considered by scientists since the late 1960s when the negative impact of the coal and petroleum chemical industryon the environment was recognized. Besides that, a shortage of fossil energy is considered a serious problem.Therefore, lignocellulosic biomass not only can ease energy and environmental problems, but also it is renewable. Furthermore all, the proposal of recycling economy and sustainable development strategies, conversion, and research in the application of natural lignocellulosic feedstock are highly valued and widely used. Because of this, lignocelluloses biotechnology has achieved rapid development in recent decades and expanded the research field significantly.

New Generation Devices for Gas (Liquid) Sensing

Because the requirements for the detection, monitoring, and transformation of environmental constituents are increasing at a significant rate developing sensor interfaces must be sensitive to low level exposures and have fast response times. As concerns about the impact of gases on health and environmental concerns increase, the reliable detection of several gases over a range of temperatures has become a priority. Included inthis group, NOx associated with air pollution, combustion, and respiratorydisease is critical. NO is the primary monitor of an asthmatic attack and can also provide rapidly accessed noninvasive disease detection. NH3, which plays an especially important role in urban environments, also is produced albeit at much lower levels, during an asthma attack. 

SOx and H2S as well as NOx play an important role in automotive and industrial exhaust, acid rain, photochemical smog, and corrosion and natural gas venting.. PH3 is an extremely toxic gas used for fumigation in agriculture and is a byproduct in the production of methamphetamines. Advances in gas sensor technology used to monitor theseexemplary gases have been driven by sensitivity, selectivity, stability,response time, and durability. Here, we review a new solid-state device technology which detects analytes by measuring an electrical property of a detection interface and from this measurement we can evaluate an interacting gas. Conductometric gas sensors can be made to consist of a sensitive interface layer decorated by nanostructure island sites.