Chemistry and Insulin-Mimetic Properties of Bis(acetylacetonate)oxovanadium(IV) and Derivatives
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- 作者：Sean S. Amin ; Kirk Cryer ; Boyan Zhang ; Subodh K. Dutta ; Sandra S. Eaton ; Oren P. Anderson ; Susie M. Miller ; Benedicte A. Reul ; Sonia M. Brichard ; and Debbie C. Crans
- 刊名：Inorganic Chemistry
- 出版年：2000
- 出版时间：February 7, 2000
- 年：2000
- 卷：39
- 期：3
- 页码：406 - 416
- 全文大小：159K
- 年卷期：v.39,no.3(February 7, 2000)
- ISSN：1520-510X
文摘
The syntheses and the solid state structural and spectroscopic solution characterizations of VO(Me-acac)2 andVO(Et-acac)2 (where Me-acac is 3-methyl-2,4-pentanedionato and Et-acac is 3-ethyl-2,4-pentanedionato) havebeen conducted since both VO(acac)2 and VO(Et-acac)2 have long-term in vivo insulin-mimetic effects instreptozotocin-induced diabetic Wistar rats. X-ray structural characterizations of VO(Me-acac)2 and VO(Et-acac)2show that both contain five-coordinate vanadium similar to the parent VO(acac)2. The unit cells for VO(Et-acac)2and VO(Me-acac)2 are both triclinic, P
, with a = 9.29970(10) Å, b = 13.6117(2) Å, c = 13.6642(2) Å, 
pha.gif" BORDER=0> =94.1770(10)
, 
= 106.4770(10), 
= 106.6350(10) for VO(Et-acac)2 and a = 7.72969(4) Å, b = 8.1856(5) Å,c = 11.9029(6) Å, pha.gif" BORDER=0> = 79.927(2), = 73.988(2), = 65.1790(10) for VO(Me-acac)2. The total concentrationof EPR-observable vanadium(IV) species for VO(acac)2 and derivatives in water solution at 20 C was determinedby double integration of the EPR spectra and apportioned between individual species on the basis of computersimulations of the spectra. Three species were observed, and the concentrations were found to be time, pH,temperature, and salt dependent. The three complexes are assigned as the trans-VO(acac)2·H2O adduct, cis-VO(acac)2·H2O adduct, and a hydrolysis product containing one vanadium atom and one R-acac- group. The reactionrate for conversion of species was slower for VO(acac)2 than for VO(malto)2, VO(Et-acac)2, and VO(Me-acac)2;however, in aqueous solution the rates for all of these species are slow compared to those of other vanadiumspecies. The concentration of vanadium(V) species was determined by 51V NMR. The visible spectra were timedependent, consistent with the changes in species concentrations that were observed in the EPR and NMR spectra.EPR and visible spectroscopic studies of solutions prepared as for administration to diabetic rats documentedboth a salt effect on speciation and formation of a new halogen-containing complex. Compound efficacy withrespect to long-term lowering of plasma glucose levels in diabetic rats traces the concentration of the hydrolysisproduct in the administration solution.
, with a = 9.29970(10) Å, b = 13.6117(2) Å, c = 13.6642(2) Å, pha.gif" BORDER=0> =94.1770(10), = 106.4770(10), = 106.6350(10) for VO(Et-acac)2 and a = 7.72969(4) Å, b = 8.1856(5) Å,c = 11.9029(6) Å, pha.gif" BORDER=0> = 79.927(2), = 73.988(2), = 65.1790(10) for VO(Me-acac)2. The total concentrationof EPR-observable vanadium(IV) species for VO(acac)2 and derivatives in water solution at 20 C was determinedby double integration of the EPR spectra and apportioned between individual species on the basis of computersimulations of the spectra. Three species were observed, and the concentrations were found to be time, pH,temperature, and salt dependent. The three complexes are assigned as the trans-VO(acac)2·H2O adduct, cis-VO(acac)2·H2O adduct, and a hydrolysis product containing one vanadium atom and one R-acac- group. The reactionrate for conversion of species was slower for VO(acac)2 than for VO(malto)2, VO(Et-acac)2, and VO(Me-acac)2;however, in aqueous solution the rates for all of these species are slow compared to those of other vanadiumspecies. The concentration of vanadium(V) species was determined by 51V NMR. The visible spectra were timedependent, consistent with the changes in species concentrations that were observed in the EPR and NMR spectra.EPR and visible spectroscopic studies of solutions prepared as for administration to diabetic rats documentedboth a salt effect on speciation and formation of a new halogen-containing complex. Compound efficacy withrespect to long-term lowering of plasma glucose levels in diabetic rats traces the concentration of the hydrolysisproduct in the administration solution.© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |