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Electron‐impact induced decomposition of some 3‐alkyl‐5‐substituted‐6‐methyl uracils
(John Wiley & Sons, 1995)
Mass spectrometry was used to study the main fragmentation routes of some 3‐alkyl‐5‐substituted‐6‐methyl uracils. Differences in fragmentation were caused by changes in the structure of the alkyl group in position 3 of the ...
Essential oil of pinus heldreichii, needles
(Taylor and Francis, 1996)
Needle oils of Pinus heldreichii Christ, produced from five different growth stages at two different locations in Serbia were examined for yield and composition during 1994. Although only ten components were identified in ...
Non-sensitized photooxygenation of some steroidal isoxazolidines
(Pergamon press, 1991)
UV irradiation of the steroidal isoxazolidines 2a, 2b, and 2c in various solvents in the presence of molecular oxygen, results in oxidative cleavage of the epoxyimino bridge to give several products; the N-unsubstituted ...
Cyclisation of alkoxy radicals. A semiempirical MNDO-PM3 study
(Royal Society of Chemistry, 1994)
The reactivity of the butoxy and 3-methylcyclohexyl radicals, as representatives of alkoxy radicals, was studied by MNDO-PM3 semiempirical MO method. In both cases it was found that the oxy radical underwent easily 1,5-H ...
Essential oil of achillea coarctata
(Taylor & Francis, 1999)
Essential oil of Achillea coarctata Poir. was investigated for yield and composition. Sixty identified compounds in the oil constituted 79-3% of the oil. The main compounds of the oil were: caryophyllene oxide (9.0%), ...
A simple approximative method for determination of Auger 1 lifetime in degenerate narrow gap semiconductors
(Elsevier, 1993)
Using the well-known Beattie-Landsberg expression for Auger 1 lifetime and the “effective” Auger energy gap (EgA), we obtained a simple approximative expression for determination of the Auger 1 lifetime. We also obtained ...
Preliminary investigation of antimicrobial activity of St. John's Wort
(Medical University Faculty of Pharmacia, 1998)
Preliminary investigations of Hypericum perforatum have shown that one of the most important activities of the plant is its antibacterial activity. The most active component of the acetonic extract has been isolated through ...
Formation of allenes by reaction of 1,4-dibromobut-2-ene with dialkyl ketones and base
(Royal Society of Chemistry, 1991)
By reaction of 1,4-dibromo-(E)-but-2-ene with dialkyl ketones and sodium hydride the allenic ketones 3 were obtained as the main products, in addition to the symmetrical unsaturated 1,8-diketones 4.
Degradative side reactions in the syntheses of exactly alternating silarylene-siloxane polymers
(Springer, 1992)
Four principal synthetic methods for preparation of exactly alternating silarylene-siloxane polymers: the chlorosilane, the acetoxysilane, the aminosilane and the ureidosilane polymerization reactions, were compared under ...
Photochemically induced mercuric oxide - iodine oxidation of some unsaturated steroid compounds
(Pergamon, 1994)
Photochemically induced HgO/I2 oxidation of cholest-5-en-3α-ol (6) and cholest-5-en-3β-ol (7) afforded (Scheme 3) products arising from the corresponding alkoxy radicals (12, 13 and 14a,b) and from attack of the I2O ...