the alternative double bonds and conjugation in the polyene compounds are one of the main properties in these compounds. each carbon-carbon bonds in a polyene compound along the chain has appreciable double-bond character. the p-electrons are therefore not localized but are relatively free to move throughout the entire carbon skeleton as an one-dimensional box. the skeleton be considered as a r...

The alternative double bonds and conjugation in the polyene compounds are one of the main properties in these compounds. Each carbon-carbon bonds in a polyene compound along the chain has appreciable double-bond character. The p-electrons are therefore not localized but are relatively free to move throughout the entire carbon skeleton as an one-dimensional box. The skeleton be considered as a r...

Convenient methods for the preparation of 1-alkoxydienes are reviewed. It is shown that 1-alkoxydienes are very reactive and can be successfully used for the synthesis of polyene compounds. These include some important natural products, such as polyene aldehydes, vitamin A aldehyde, the ethers and esters of vitamin A, f3-ionolidenacetaldehyde, f3-C,9-aldehyde and other related compounds. A conv...

a major group of drugs that have been approved for the therapy of systemic fungal infections are polyene antibiotics. amphotericin b (amb), one of the polyene antibiotics, has been used to treat serious systemic fungal infections by binding to sterols such as ergosterol in fungal cells membrane, and is believed to form pores in the membrane and create a transmembrane ion-channel. since all euka...

one of the useful indices in molecular topology is randić index. the alternative double bonds andconjugation in the polyene compounds are one of the main properties in these compounds. someof the molecular orbital and structural properties refer to this specialty, such as: molar absorptioncoefficient (εmax) , electrical conductivity and difference energy level of the homo and lumoorbitals, etc....

Strains of Saccharomyces cerevisiae FL200 capable of growing on a solid medium containing a mixture of polyene macrolide antibiotics (nystatin, 40 micrograms/ml, amphotericin B, 40 micrograms/ml, pimaricin, 150 micrograms/ml and RP9971 antibiotic, 10 micrograms/ml) have been isolated after successive selection steps. The mutant strains, PR13 and PRC24, are 10 to 100 times more resistant than th...

The conjugated polyenes 10, 11, and 17 respectively, with 9anthryland 2-tetraphenylporphyrinyl (TPP) terminal groups and a bicyclooctane unit incorporated into the polyene chain were synthesized by Wittig olefinations. In all cases it was possible to obtain the all-(4 compounds from the (Q/(Z)-isomeric mixtures by chromatographic purification and several recrystallizations. From the UV/Vis spec...

The rimJ gene, which codes for a crotonyl-CoA carboxylase/reductase, lies within the biosynthetic gene cluster for two polyketides belonging to the polyene macrolide group (CE-108 and rimocidin) produced by Streptomyces diastaticus var. 108. Disruption of rimJ by insertional inactivation gave rise to a recombinant strain overproducing new polyene derivatives besides the parental CE-108 (2a) and...

A major group of drugs that have been approved for the therapy of systemic fungal infections are polyene antibiotics. Amphotericin B (AmB), one of the polyene antibiotics, has been used to treat serious systemic fungal infections by binding to sterols such as ergosterol in fungal cells membrane, and is believed to form pores in the membrane and create a transmembrane ion-channel. Since all euka...

Scalemic bromonium ions generated enantiospecifically by the action of catalytic triflic acid on scalemic regioisomeric bromohydrin derivatives are trapped intramolecularly, enantiospecifically and regioselectively to give bicyclic brominated carbocycles in excellent yield and high enantiomeric excess. This enantiospecific pathway is not significantly perturbed by the addition of a trisubstitut...