Cycloaddition d'ylures d'azométhine dérivés de la 3,4-dihydro-6,7-diméthoxy-3-méthoxycarbonyl-isoquinoléine

1991 ◽  
Vol 69 (7) ◽  
pp. 1156-1160 ◽  
Author(s):  
Tahar Lakhlifi ◽  
Ahmed Sedqui ◽  
Bernard Laude ◽  
Nguyen Dinh An ◽  
Joël Vebrel
Keyword(s):  
Magnetic Resonance ◽  
Key Words ◽  
Proton Magnetic Resonance ◽  
Azomethine Ylide ◽  
Magnetic Resonance Data ◽  
Resonance Data ◽  
Azabicyclic Compounds ◽  
Derivatives Of ◽  
Proton Magnetic Resonance Data

Three azomethine ylide precursors including the methyl 3,4-dihydro-6,7-dimethoxyisoquinoline-3carboxylate moiety were synthesized. The 1,3-dipolar species formed from these products react with activated dipolarophilic olefines leading diastereospecifically to derivatives of 4′,5′-dimethoxy-1,2-benzo-4,7-imino-4-methoxycarbonyl-1-cycloheptene. Proton magnetic resonance data allowed the determination of the stereochemistry of the cycloadducts. Key words: cyclic azomethine ylide, azabicyclic compounds, stereochemistry.

Polybrominated derivatives of 5α-androstane and 5α-estrane 3-ketones: cyclopropanol formation

1976 ◽  
Vol 54 (18) ◽  
pp. 2865-2870 ◽  
Author(s):  
J. F. Templeton ◽  
C. W. Wie ◽  
F. E. Hruska
Keyword(s):  
Magnetic Resonance ◽  
Sodium Borohydride ◽  
Proton Magnetic Resonance ◽  
Spectroscopic Methods ◽  
Borohydride Reduction ◽  
Magnetic Resonance Data ◽  
Resonance Data ◽  
Sodium Borohydride Reduction ◽  
Derivatives Of ◽  
Proton Magnetic Resonance Data

Bromohydrin acetates from sodium borohydride reduction of di- and tribrominated 17β-hydroxy-5α-androstan-3-one and 17β-hydroxy-5α-estran-3-one have been prepared and their structures determined by spectroscopic methods. Some 220 MHz proton magnetic resonance data are reported for structure determination. The formation of cyclosteroid derivatives by 1,3-elimination of bromine with zinc–copper couple is discussed.

Proton magnetic resonance studies of 2′-deoxynucleosides and nucleotides in the syn conformation

1978 ◽  
Vol 56 (9) ◽  
pp. 1170-1176 ◽  
Author(s):  
Arthur L. George ◽  
Frank E. Hruska ◽  
Kelvin K. Ogilvie ◽  
Antonin Holy
Keyword(s):  
Magnetic Resonance ◽  
Proton Magnetic Resonance ◽  
Repulsive Interaction ◽  
Nucleotide Level ◽  
Magnetic Resonance Studies ◽  
Magnetic Resonance Data ◽  
Resonance Data ◽  
Sugar Ring ◽  
Derivatives Of ◽  
Proton Magnetic Resonance Data

Proton magnetic resonance data for 6-methyl-2′-deoxyuridine and its 3′- and 5′-monophosphate derivatives are obtained in aqueous solution and compared with data for corresponding thymine derivatives. The data show that the derivatives of the 6-methyluracil base occupy the syn conformation. The presence of the syn base leads to a flattening of the sugar ring and destabilization of the g+ conformer about the C(4′)—C(5′) bond. This destabilization is particularly large at the 5′-nucleotide level and is discussed in terms of a repulsive interaction involving the 2-keto oxygen of the base and the negatively charged 5′-group.

A Comparative Proton Magnetic Resonance Study of the Molecular Conformation of Uracil and 6-Aza Uracil Nucleosides and Nucleotides

1973 ◽  
Vol 51 (15) ◽  
pp. 2571-2577 ◽  
Author(s):  
Donald J. Wood ◽  
Frank E. Hruska ◽  
Richard J. Mynott ◽  
Ramaswamy H. Sarma
Keyword(s):  
Magnetic Resonance ◽  
Proton Magnetic Resonance ◽  
Molecular Conformation ◽  
Three Dimensional ◽  
Magnetic Resonance Study ◽  
Magnetic Resonance Data ◽  
Ribose Phosphate ◽  
Resonance Data ◽  
Proton Magnetic Resonance Study ◽  
Proton Magnetic Resonance Data

Proton magnetic resonance data for uridine and uridine-5′-monophosphate, and the corresponding 6-azauracil analogs, are presented and discussed in terms of their overall three dimensional conformations in aqueous solution. The data reveal a destabilizing influence of the 6-aza base upon the gog and g′–g′ conformation of the ribose phosphate moiety.

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