The dehalogenation of a-haloketones and a-halocarbonyl compounds is an inevitable proce­ dure for the organic synthesis and these reductive dehalogenations have been often effected in organic syntheses. There have been various procedures for the purpose and these are obtained by zinc and acetic acid [1], sodium dithionite [2], titanium(III) chloride [3], organotin hydride [4], sodium hydrogen t...

On the basis of the relationship between the fluorescence characteristics of the benzofurazan compounds and the Hammett constants (sigma p), a new fluorescence Edman reagent, 7-methylthio-4-(2,1,3-benzoxadiazolyl) isothiocyanate (MTBD-NCS) was designed and synthesized. MTBD-thiohydantoin (TH)-amino acid derivatives produced by the Edman sequencing method gave fluorescence, whereas other degrada...

Determination of microalgaes' fatty acid content is often done with chloroform and methanol according to the Bligh and Dyer extraction, though faster methods exist. A number of comparisons between the Bligh and Dyer and faster methods have resulted in contradicting data, possibly due to differences in algae used and the different versions of the Bligh and Dyer method applied. Here, various form...

Paper cultural heritages are valuable historical records and also abound in resources. Due to its organic property, paper is susceptible aging, destruction by environmental pollution human factors. At present, many countries the world facing problem of conservation. Coating reinforcement one methods for conservation, which choice reinforcing resin key. A transparent polyurethane, based on epoxy...

A semi-automatic method for the simultaneous determination of the sequence and the d/l-configuration of amino acids in peptides is reported. The automated sequencing program was set up based both on the yield in the cyclization/cleavage reaction with 40 mmol dm23 boron trifluoride (BF3) etherate at 48 °C for 5 min and on the recovery of anilinothiazolinone(ATZ-) amino acids extracted with ethyl...

A complete series of eight 1,6:2,3- and 1,6:3,4-dianhydro-β-D-hexopyranoses were subjected to fluorination with DAST. The 1,6:3,4-dianhydropyranoses yielded solely products of skeletal rearrangement resulting from migration of the tetrahydropyran oxygen (educts of D-altro and D-talo configuration) or of the 1,6-anhydro bridge oxygen (D-allo, D-galacto). The major products yielded by the 1,6:2,3...