Results 141 to 150 of about 16,341 (199)

Quantum interference in polyenes

The Journal of Chemical Physics, 2014
The explicit form of the zeroth Green's function in the Hückel model, approximated by the negative of the inverse of the Hückel matrix, has direct quantum interference consequences for molecular conductance. We derive a set of rules for transmission between two electrodes attached to a polyene, when the molecule is extended by an even number of carbons
Yuta Tsuji, Roald Hoffmann, Ramis Movassagh, Supriyo Datta   +3 more
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Polyene Macrolide Antibiotic Biosynthesis

Current Medicinal Chemistry, 2004
Polyenes constitute a large class of natural metabolites produced by giant multifunctional enzymes in a process resembling fatty acid biosynthesis. Like fatty acids, polyene macrolides and other polyketides are assembled by decarboxylative condensations of simple carboxylic acids.
J F, Aparicio, M V, Mendes, N, Antón, E, Recio, J F, Martín   +4 more
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Bio-inspired polyene cyclization: aziridinyl polyene cyclization catalyzed by InBr3

Chemical Communications, 2009
This communication describes a highly efficient aziridinyl polyolefin cyclization catalyzed by InBr(3) to synthesize chiral terpenoid bearing a 3-amino group in the A ring; both good yields and excellent asymmetric induction were achieved.
Yu-Jun, Zhao, Li-Jun Serena, Tan, Bin, Li, Si-Min, Li, Teck-Peng, Loh   +4 more
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The Polyene Antifungal Antibiotics

1963
During the early 1950’s there appeared reports, from time to time of the presence among the products elaborated by actinomycetes of antifungal antibiotics which exhibited very similar and very characteristic multipeaked ultraviolet absorption spectra. In 1954, with a good number of examples on record, these spectra were analyzed and identified as those
W, OROSHNIK, A D, MEBANE
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Polyenic compounds Communication 2. Polyenic compounds containing heterocyclic substituents

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1956
1. In the reactions of 2-pyridylmethyllithium and of 2-quinolylmethyllithium with 3-methyl-6-phenyl-3, 5-hexadien-2-one, the corresponding tertiary alcohols were formed. Dehydration of these gave 2, 3-dimethyl-6-phenyl-1-(2-pyridyl)-1, 3, 5-hexatriene and 2, 3-dirnethyl-6-phenyl-1-(2-quinolyl)-1, 3, 5-hexatriene. 2.
B. M. Mikhailov, G. S. Ter-Sarkisyan
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Über einige neue Polyen‐diketone und Polyen‐diketo‐carbonsäuren

Helvetica Chimica Acta, 1954
AbstractDurch Kondensation von Diacetyl mit Monoaldehyd‐fumarsäuremethylester und Muconsäure‐monoaldehyd‐monomethylester wurden verschiedene Polyen‐diketo‐carbonsäureester dargestellt und ihre UV.‐Absorptionsspektren verglichen.
G. Pictet, P. Karrer
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Polyenes Communication 5. Synthesis of unsymmetrical diaryl polyenic hydrocarbons

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1959
1. By the reaction of the Grignard reagent from α-chloro-p-xylene with polyethoxyphenylalkanes C6H5-[CH(OC2H5-CH2]n-CH(OC2H5)2 polyethoxyphenyl-p-tolylalkanes are formed: C6H5 -[CH(OC2H5)-CH2)]n+1 -C6H4-CH3-p 2. By the action of aqueous-alcoholic hydrogen bromide these are converted into phenyl-p-tolyl polyenes C6H5-(CH=CH)n+1−-C6H4-CH3 ...
B. M. Mikhailov, L. S. Povarov
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Polyene Antibiotics

Science, 1955
W, OROSHNIK, L C, VINING, A D, MEBANE, W A, TABER   +3 more
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Polyen

1958
de Budé Guy. Polyen. In: Bulletin de l'Association Guillaume Budé : Lettres d'humanité, n°17, décembre 1958. pp. 21-29.
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Polyenes

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1960
B. M. Mikhailov, G. S. Ter-Sarkisyan
openaire   +1 more source