Reaction of ethyl cyanoacetate with benzal-4-acetylanilines: An unexpected result

778-780Reaction of ethyl cyanoacetate with benzal-4-acetylanilines 1a-10a, the compounds containing both azomethine and ketone linkages, in equimolar ratio, in the presence of pyridine yields solid products, which have been characterized as ethyl benzalcyanoacetate and its derivatives 1b-10b on the basis of elemental analysis and spectral studies. The reaction of 1a-10a with two moles of ethyl cyanoacetate also results in the formation of the same products 1b-10b, by an unexpected attack of ethyl cyanoacetate on azomethine linkage only rather than on both the reactive centres i.e. carbon-nitrogen double bond and carbon-oxygen double bond

Condensation of dimethyl malonate with benzal-4-acetylanilines: A chemoselective reaction

735-736Dimethyl malonate has reacted chemoselectively with carbon-nitrogen double bond of benzal-4-acetylanilines (1-8) leaving the carbon-oxygen double bond, considered to be more reactive, intact under reaction conditions, leading to the formation of mono addition-elimination products rather than bis attack at both the double bonds, even when the reaction has been carried out with two moles of dimethyl malonate

Chemoselective reaction of malononitrile with imine-ones and antifungal potential of products

247-250Condensation of malononitrile with 1-[4-(benzyl­idene­amino)­phenyl]ethanones 1-10, the compounds containing both carbon-nitrogen and carbon-oxygen double bonds, in equimolar ratio results in the formation of solid products, identified as 2-benzylidenemalononitrile and its derivatives 1a-10a on the basis of elemental analysis and spectral studies. The reaction of 1-10 with two moles of malononitrile also yields the same products 1a-10a by a chemoselective attack of malononitrile on carbon-nitrogen double bond only rather than on both the reactive centres. The synthesized compounds 1a-10a have been evaluated for antifungal potential against Alternaria alternata, Colletotrichum capsici, Fusarium oxysporum, Myrothecium roridum and Ustilago tritici. Some of the compounds have been found to possess promising antifungal potential against the test fungi

Optimisation of rice straw and acacia biochar doses in two soils for phosphorus availability

Biochar (BC) is a soil fertility enhancer, regarded as a potential carbon sequester and nutrient leaching preventer. Various studies have shown better phosphorus (P) availability with adding biochar. However, limited reporting is available on absorption–desorption behaviour of added P and dose optimisation of biochar. Rice straw biochar (RSB) and acacia biochar (ACB), prepared by slow pyrolysis at optimised temperature and pyrolysis time, were incubated at different rates (0, 5, and 10 g kg−1) in loamy sand and clay loam soils to study P sorption compared to the unamended control. The data was observed to be best fitted into Langmuir adsorption isotherm for P adsorption. The effects on maximum P adsorption, bonding energy, and adsorption rate constants were lower in loamy sand compared to clay loam soil. The values of maximum P desorption (Dm) and desorption rate constant (Kd) decreased with the application of biochar. A linear regression equation optimised the amount of P addition for soil amendments. For the soil with inherent P content, rice biochar was the best option (5 g kg−1), while for soils lacking in P, ACB is optimised at 5 g kg−1 with external P input of 1 mg P kg−1 of test soil. This data can be recommended to the farmers as a best practice for the P addition, along with managing farm wastes as biochars to enhance nutrient availability

The Role of Cdk5 in Neuroendocrine Thyroid Cancer

Medullary thyroid carcinoma (MTC) is a neuroendocrine cancer that originates from calcitonin-secreting parafollicular cells, or C cells. We found that Cdk5 and its cofactors p35 and p25 are highly expressed in human MTC and that Cdk5 activity promotes MTC proliferation. A conditional MTC mouse model was generated and corroborated the role of aberrant Cdk5 activation in MTC. C cell-specific overexpression of p25 caused rapid C cell hyperplasia leading to lethal MTC, which was arrested by repressing p25 overexpression. A comparative phosphoproteomic screen between proliferating and arrested MTC identified the retinoblastoma protein (Rb) as a crucial Cdk5 downstream target. Prevention of Rb phosphorylation at Ser807/Ser811 attenuated MTC proliferation. These findings implicate Cdk5 signaling via Rb as critical to MTC tumorigenesis and progression.National Institutes of Health (U.S.) (Grant NS051874)Howard Hughes Medical Institut

The Role of Cdk5 in Neuroendocrine Thyroid Cancer

Medullary thyroid carcinoma (MTC) is a neuroendocrine cancer that originates from calcitonin-secreting parafollicular cells, or C cells. We found that Cdk5 and its cofactors p35 and p25 are highly expressed in human MTC and that Cdk5 activity promotes MTC proliferation. A conditional MTC mouse model was generated and corroborated the role of aberrant Cdk5 activation in MTC. C cell-specific overexpression of p25 caused rapid C cell hyperplasia leading to lethal MTC, which was arrested by repressing p25 overexpression. A comparative phosphoproteomic screen between proliferating and arrested MTC identified the retinoblastoma protein (Rb) as a crucial Cdk5 downstream target. Prevention of Rb phosphorylation at Ser807/Ser811 attenuated MTC proliferation. These findings implicate Cdk5 signaling via Rb as critical to MTC tumorigenesis and progression.National Institutes of Health (U.S.) (Grant NS051874)Howard Hughes Medical Institut