Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
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Target Concepts:
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Query: UMLS:C1832526 (
PCC
)
5,967
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The syntheses of three classes of C-3 perfluoroalkyl substituted steroids are described. They are the 3 beta-hydroxy-3 alpha-perfluoroalkylandrost-4-en-17-ones (5a-c), 3-perfluoroalkylandrosta-3,5-dien-3-ones (8a-c) and 3 beta-hydroxy-3 alpha-perfluoroalkylandrost-5-en-17-ones (12a-c). Addition of a series of perfluoroalkylorganometallic reagents (RFLi; RF = C2F5, C3F7, or C4F9) to the 3 position of silylated testosterone 2b afforded
delta 4
perfluoroalkyl carbinols 3. In Scheme 1, deprotection with HF and oxidation at the C-17 carbon with
PCC
produced
delta 4
ketones 5. In Scheme 2 dehydration of 3 with 1,2-phenylenephosphorochloridite and iodine afforded delta 3,5 dienes 6 which were deprotected and oxidized as above to the C-17 ketones 8. In Scheme 3 isomerization of the double bond of 3 from the C-4 to the C-5 position using the allylic halogenation followed by treatment with lithium aluminum hydride led to the synthesis of the double bond isomer series 12. A new method for dehydration was developed. On average and within experimental error, 3 beta-hydroxy-3 alpha-perfluoroalkylandrost-5-en-17 ones (12a-c) were better than the 3-perfluoroalkylandrosta-3,5-dien-17-ones (8a-c) and 3 beta-hydroxy-3 alpha-perfluoroalkylandrost-4-en-17-ones (5a-c) at inhibiting glucose-6-phosphate dehydrogenase.
...
PMID:The syntheses of 3-substituted perfluoroalkyl steroids. 875 Apr 32
A mutant (Delta5) of Synechocystis sp. strain
PCC
6803 constructed by inactivating five inorganic carbon sequestration systems did not take up CO(2) or HCO(3)(-) and was unable to grow in air with or without glucose. The
Delta4
mutant in which BicA is the only active inorganic carbon sequestration system showed low activity of HCO(3)(-) uptake and grew under these conditions but more slowly than the wild-type strain. The Delta5 mutant required 1.7% CO(2) to attain half the maximal growth rate. Electron transport activity of the mutants was strongly inhibited under high light intensities, with the Delta5 mutant more susceptible to high light than the
Delta4
mutant. The results implicated the significance of carbon sequestration in dissipating excess light energy.
...
PMID:Properties of mutants of Synechocystis sp. strain PCC 6803 lacking inorganic carbon sequestration systems. 1878 96