Synthesis and Assignment of Absolute Configuration to the N6-Deoxyadenosine Adducts Resulting from Cis and Trans Ring-Opening of Phenanthrene 9,10-Oxide
摘要:
Reaction of calf thymus DNA with phenanthrene 9,10-oxide in vitro results in alkylation of the exocyclic amino groups of the purine bases. Adducts result from both cis and trans opening of the epoxide. In the present study, structures of the N-6-deoxyadenosine adducts have been unequivocally assigned by synthesis from optically pure cis- and trans-9-amino-10-hydroxy-9,10-dihydrophethrene. Resolution of trans-9-azido-10-hydroxy-9,10-dihydrophenanthrene as its acetate was achieved on a chiral. HPLC column. The early-eluting (-)-enantiomer was assigned (9R,10R)-absolute configuration based on a characteristic negative CD band at 232 nm due to the helicity of its biphenyl chromophore, in combination with a H-1 NMR coupling constant that indicated pseudodiaxial orientation of the substituents at C-9 and C-10. Aminolysis of the ester followed by reduction of the azido group provided the desired, optically active trans (9R,10R) amino alcohol. As a starting material for synthesis of the cis amino alcohol, trans-9-bromo-10-acetoxy-9,10-dihydrophe was resolved by chiral HPLC. As above, the early-eluting (-)-enantiomer was assigned (9R,10R)absolute configuration based on a characteristic negative CD band at 234 nm. Displacement of bromine with inversion of configuration by azide, aminolysis of the ester, and reduction provided optically pure cis-(9S,10R)-9-amino-10-hydroxy-9,10-dihydrophenanthrene. Coupling of the optically active amino alcohols with 6-fluoro-9-(2-deoxy-beta-D-erythro-pentofuranosyl) purine (the 6-fluoro analog of dA) yielded the corresponding N-6-deoxyadenosine adducts. Comparison of CD spectra and HPLC retention times of the synthetic adducts with those of the adducts obtained from calf thymus DNA make it possible to assign unambiguously the structures of the DNA adducts.
Synthesis and Assignment of Absolute Configuration to the N6-Deoxyadenosine Adducts Resulting from Cis and Trans Ring-Opening of Phenanthrene 9,10-Oxide
摘要:
Reaction of calf thymus DNA with phenanthrene 9,10-oxide in vitro results in alkylation of the exocyclic amino groups of the purine bases. Adducts result from both cis and trans opening of the epoxide. In the present study, structures of the N-6-deoxyadenosine adducts have been unequivocally assigned by synthesis from optically pure cis- and trans-9-amino-10-hydroxy-9,10-dihydrophethrene. Resolution of trans-9-azido-10-hydroxy-9,10-dihydrophenanthrene as its acetate was achieved on a chiral. HPLC column. The early-eluting (-)-enantiomer was assigned (9R,10R)-absolute configuration based on a characteristic negative CD band at 232 nm due to the helicity of its biphenyl chromophore, in combination with a H-1 NMR coupling constant that indicated pseudodiaxial orientation of the substituents at C-9 and C-10. Aminolysis of the ester followed by reduction of the azido group provided the desired, optically active trans (9R,10R) amino alcohol. As a starting material for synthesis of the cis amino alcohol, trans-9-bromo-10-acetoxy-9,10-dihydrophe was resolved by chiral HPLC. As above, the early-eluting (-)-enantiomer was assigned (9R,10R)absolute configuration based on a characteristic negative CD band at 234 nm. Displacement of bromine with inversion of configuration by azide, aminolysis of the ester, and reduction provided optically pure cis-(9S,10R)-9-amino-10-hydroxy-9,10-dihydrophenanthrene. Coupling of the optically active amino alcohols with 6-fluoro-9-(2-deoxy-beta-D-erythro-pentofuranosyl) purine (the 6-fluoro analog of dA) yielded the corresponding N-6-deoxyadenosine adducts. Comparison of CD spectra and HPLC retention times of the synthetic adducts with those of the adducts obtained from calf thymus DNA make it possible to assign unambiguously the structures of the DNA adducts.
On the regioselectivity in transformation of benzo[a]pyrene 4,5-oxide and 3-methylcholanthrene 11,12-oxide to the corresponding β-amino-alcohol d
作者:Jochanan Blum、Merav Setty-Fichman、Lea Efron、Sason Shaik、Ronald G. Harvey
DOI:10.1016/s0040-4020(01)85570-8
日期:1994.1
beta-Amino-alcohol derivatives of benzo[a]pyrene and 3-methylcholanthrene, 8, 9 and 15 which are assumed to take part in the transformation of the K-region oxides 1 and 10 to the corresponding arene imines, have been prepared. The sequence of reactions consists of nucleophilic oxirane ring opening of the epoxides by azide ion, acetylation of the separated isomeric trans-azido alcohols so formed, and palladium catalyzed hydrogenation of the resulting beta-acetyloxy azides under ambient conditions. The ratios between the isomeric azido-hydrins obtained from 1 and 10, as well as the product distribution in azide-induced oxirane ring cleavage in other carbocyclic and heterocyclic arene oxides have been shown to correlate with Huckel-type calculations of Wheland's pi-localization energies.
Shudo,K.; Okamoto,K., Chemical and pharmaceutical bulletin, 1976, vol. 24, # 5, p. 1013 - 1015
作者:Shudo,K.、Okamoto,K.
DOI:——
日期:——
Synthesis and Assignment of Absolute Configuration to the N6-Deoxyadenosine Adducts Resulting from Cis and Trans Ring-Opening of Phenanthrene 9,10-Oxide
作者:Mahesh K. Lakshman、Wei Xiao、Jane M. Sayer、Albert M. Cheh、Donald M. Jerina
DOI:10.1021/jo00086a027
日期:1994.4
Reaction of calf thymus DNA with phenanthrene 9,10-oxide in vitro results in alkylation of the exocyclic amino groups of the purine bases. Adducts result from both cis and trans opening of the epoxide. In the present study, structures of the N-6-deoxyadenosine adducts have been unequivocally assigned by synthesis from optically pure cis- and trans-9-amino-10-hydroxy-9,10-dihydrophethrene. Resolution of trans-9-azido-10-hydroxy-9,10-dihydrophenanthrene as its acetate was achieved on a chiral. HPLC column. The early-eluting (-)-enantiomer was assigned (9R,10R)-absolute configuration based on a characteristic negative CD band at 232 nm due to the helicity of its biphenyl chromophore, in combination with a H-1 NMR coupling constant that indicated pseudodiaxial orientation of the substituents at C-9 and C-10. Aminolysis of the ester followed by reduction of the azido group provided the desired, optically active trans (9R,10R) amino alcohol. As a starting material for synthesis of the cis amino alcohol, trans-9-bromo-10-acetoxy-9,10-dihydrophe was resolved by chiral HPLC. As above, the early-eluting (-)-enantiomer was assigned (9R,10R)absolute configuration based on a characteristic negative CD band at 234 nm. Displacement of bromine with inversion of configuration by azide, aminolysis of the ester, and reduction provided optically pure cis-(9S,10R)-9-amino-10-hydroxy-9,10-dihydrophenanthrene. Coupling of the optically active amino alcohols with 6-fluoro-9-(2-deoxy-beta-D-erythro-pentofuranosyl) purine (the 6-fluoro analog of dA) yielded the corresponding N-6-deoxyadenosine adducts. Comparison of CD spectra and HPLC retention times of the synthetic adducts with those of the adducts obtained from calf thymus DNA make it possible to assign unambiguously the structures of the DNA adducts.