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Organic geochemical study of the "W" oil-gas field in the Yugoslav part of the Pannonian basin
(Organic Geochemistry, 1990)
The naphthenic crude oil from the "W" oil-gas field differs from almost all other, paraffinic base oils discovered until now in the Yugoslav part of the Pannonian basin. In order to explain this difference, some geological ...
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.
Semisynthesis of Taxol (R): an improved procedure far the isolation of 10-deacetylbaccatin III
(Serbian Chemical Soc, Belgrade, 1999)
From the needles of domestic yew, (Taxus baccata), 10-deacetylbaccatin III (10-DAB) call be isolated in quantities of up to 297 mg per kg of fresh needles. Additional quantities of 10-DAB call be obtained from the extract ...
Highly oxygenated guaianolides from Anthemis carpatica
(American Chemical Society (ACS), 1997)
Twelve new guaianolides, (1-12), six of them (2-5, 9 and 12) containing a hydroperoxy function, were isolated from the aerial parts of the flowering plant Anthemis carpatica. Their structures were elucidated by spectroscopic ...
Oxidation products of hyperforin from Hypericum perforatum
(Elsevier, 1998)
The isolation of two oxidation products of hyperforin from the aerial parts of Hypericum perforatum and their structure determination by means of 2D NMR methods is reported. The products had the same 1-(2-methyl-1- ...
Oxygen reduction on Au (100) and vicinal Au (910) and Au (11, 1, 1) faces in alkaline solution. A rotating disc-ring study
(Elsevier, 1992)
The kinetics of oxygen reduction have been studied on Au (100) and vicinal Au (910) and Au (11, 1, 1) faces in 0.1 M NaOH by a rotating disc-ring method. A very high activity of these surfaces for O2 reduction was demonstrated. ...
Experimental determination of silicon pressure sensor diaphragm deflection
(Elsevier, 1990)
A method is presented for the accurate determination of the deflection of diaphragms commonly used for miniature piezoresistive and capacitive pressure sensors. The method utilizes a well-known apparatus for thin-film ...
Functionalized oligopolysiloxanes by heterogeneously catalyzed equilibration polymerization reactions
(Springer, 1995)
A new general procedure for preparation of functionalized oligopolysiloxanes of predetermined molecular weight is described. It utilizes heterogeneously catalyzed siloxane equilibration polymerization reactions which do ...
An improved approach to B-norsteroids: An one-pot preparation of 3β-acetoxy-5-oxo-5,6-seco-cholestan-6-oic and 3β-acetoxy-5,17-dioxo-5,6-seco-androstan-6-oic acids
(Serbian Chemical Society, 1998)
A simple one-put procedure for the synthesis of the 5,6-seco-steroidal acids 9a,b in described in this paper. It consists of the epoxidation of the ▲ 5 -steroids, i.e., cholesteryl acetate (8a) and 17-oxo-aandrost-5-en-3β-yl ...