A convenient and efficient regioselective synthesis of phosphorylated 3-(β-hydroxy) allenes by an atom economical [2,3]-sigmatropic rearrangement of the mediated propargyl phosphite or phosphinite which can be readily prepared via reaction of protected 5-(tetrahydro-2H-pyran-2-yloxy)-hex-1-yn-3-ol with dimethyl chlorophosphite or chlorodiphenyl phosphine, respectively, is described. This paper discusses a reaction of phosphorylated 3-(β-hydroxy)allenes with protected or unprotected hydroxy group involving 5-endo-trig cyclization or 2,3-addition. Reaction of 3-(β-hydroxy) allenephosphonates with electrophiles that produces 2-oxo-2,5-dihydro-1,2-oxaphos pholes due to the participation of the phosphonate neighboring group in the cyclization is described. On the other hand, 5-hydroxyhex-(1E)-enyl phosphine oxides were prepared by chemo-, regio-, and stereoselective electrophilic addition to the C 2 -C 3 double bond in the allenyl phosphine oxides and subsequent attack of the external (chloride anion) nucleophile. Phosphorylated 3-(β-hydroxy)allenes were smoothly converted into the corresponding 2-phosphoryl-5,6-dihydro-2H-pyrans by using 5 mol % of coinage metal salt as catalyst in 6-endo-trig cycloisomerization reaction.

Antioxidant activity of the peptides derived from proteins of defatted cottonseed kernels and cotton ground oil-cake by their enzymatic hydrolysis with acidic (Asp. niger) and neutral proteinases (Bac. amyloliquefaciens) was studied. Antioxidant activity of the derived peptides depended on the used proteins and enzymes. The peptides derived by using of neutral proteinase possessed higher antioxidant activity, in comparison with the peptides derived by acidic proteinases.

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Abstract:Inhibitors of pancreatic α-amylase offer an effective strategy to lower the levels of postprandial hyperglycemia by control of starch breakdown. Among 86 fungal endophytes isolated from 15 medicinal plants Aspergillus terreus-AF104S, Aspergillus egypticus-HT166S and Penicillium sp.-CC200 exhibited strong pancreatic amylase inhibitory potential were selected. Endophytes were subjected to ethyl acetate extraction and tested for α-amylase inhibition, in order to assess and evaluate their inhibitory potential on pancreatic α-amylase. Analysis showed concentration dependent enzyme inhibition up to 83% with half inhibition (IC50) values for less 25 mg⋅mL -1 , which is lower than acarbose as control. It was observed 3-fold increasing of V max and maintenance K m at control level in the presence of extracts A. terreus-AF104S and Penicillium sp.-CC200, while in presence of extract A. egypticus-HT166S K m was doubled, and V max was maintained at the control level. Kinetic studies allow proposing the competitive mode of α-amylase inhibition by extracts A. egypticus-HT166S and uncompetitive inhibition by extracts A. terreus-AF104S and Penicillium sp.-CC200.