Претраживање
Приказ резултата 1-10 од 12
Some Observations Concerning 1H‐NMR. Spectra of 5‐hydroxy‐ and 5‐acetoxy‐steroid compounds
(Wiley-Blackwell, 1981)
It was found that analysis of the 1H‐NMR. signals (at 360 (preferably) and/or 100 MHz) of the protons at C (4) and of the equatorial α‐proton at C (6), particularly when these are located in the 2–3 ppm region and therefore ...
Synthesis, structure, and reactivity of secosteroids containing a medium‐sized ring. Part 32. Conformations and photochemical reactivity of some unsaturated 5,10‐secosteroidal ketones
(Wiley - VCH Verlag GmbH & Co, 1991)
UV irradiation of the unsaturated (E)‐5,10‐secosteroidal ketones 1 and 6 results, in addition to (E/Z)‐isomerization, in an intramolecular Pateino‐Büchi reaction and, in the case of 1, in transannular cyclization (along ...
Regularity of Intermittent Bursts in Briggs Symbol of the Klingon Empire Rauscher Oscillating Systems with Phenol
(Wiley-V C H Verlag Gmbh, Weinheim, 2014)
The intermittency or intermittent bursting as the type of dynamic state when two qualitatively different behaviors replace one another randomly during the course of the reaction, although all the control parameters remain ...
Oxidative Fragmentations of the 5-alpha and 5-beta-Hydroxy-B-norcholestan-3-beta-yl Acetates
(Wiley, 2003)
Oxidations of 5α‐hydroxy‐B‐norcholestan‐3β‐yl acetate (8) with Pb(OAc)4 under thermal or photolytic conditions or in the presence of iodine afforded only complex mixtures of compounds. However, the HgO/I2 version of the ...
Conformations of the Nine-Membered Ring in the B-Nor-5,10-secosteroids. X-Ray and NMR Analysis
(Wiley, 2005)
The conformations of (Z)‐ and (E)‐5‐oxo‐B‐nor‐5,10‐secocholest‐1(10)‐en‐3β‐yl acetates (2 and 3, resp.) were examined by a combination of X‐ray crystallographic analysis and NMR spectroscopy, with emphasis on the geometry ...
13,14-Seco-steroids: A New Type of Modified Steroids Containing a Nine-Membered Ring
(Wiley, 1999)
Oxidations of 14α‐hydroxy‐5α‐cholestan‐3β‐yl acetate (5) with lead tetraacetate under thermal or photolytic conditions or in the presence of iodine proceed mainly by fragmentation of the C(13)−C(14) bond to give as the ...
Opening of the Macrocyclic Ring in 5,10:8,9‐Disecosteroids ( = Steroklastanes)
(Weinheim : Wiley-VCH Verlag GmbH & Co., 1992)
Catalytic hydrogenation of the Δ3‐unsaturated (9R,10 R)‐ and (9S,10 S)‐epoxyenol lactones 3a, b., and 4a, b., respectively, affords, in addition to the expected saturated epoxylactones 5a, b and 7a, b, also open‐chain ...
Photolysis of Steroidal 20-Aryl-Substituted 11-Nitrites
(Wiley, 1997)
The two structurally similar 20‐phenyl‐ and 20‐(4‐methoxyphenyl)‐11‐(nitrosooxy)pregnan‐20‐ol derivatives 4 and 7 behave differently under photolytic conditions, the former nitrous acid ester affording, as a main product, ...
The Reductive Conversion of Some Cyclic and Acyclic vic-Epoxides to Alcohols by Means of Lithium Aluminium Hydride/Aluminium Trichloride
(Wiley, 1985)
Unsubstituted medium‐ring 1,2‐epoxycycloalkanes and certain vic‐epoxyalkanes are reduced to the corresponding alcohols very slowly when LiAlH4 alone is used as reducing agent. However, the combination of LiAlH4 and AlCl3, ...
The Reduction of Some 1, 2‐Epoxides with Lithium Aluminium Hydride. Preliminary Communication
(Wiley - VCH Verlag GmbH & Co, 1976)
The factors influencing the ease of the lithium aluminium hydride reduction of various 1,2‐epoxycycloalkanes and 1,2‐epoxyalkanes are described and discussed.