0000000000308854
AUTHOR
Rosina Rainieri
Synthesis and spectroscopic characterizations of both 1-ethyl-4,8-dihydro-10-methoxy-3-methyl-8-r1-6-r2-dipyrazolo[3,4-b:4′,3′-f]-[1,5]diazocin-5(1H)-ones and 1-ethyl-1,4,8,9-tetrahydro-3,9-dimethyl-8-r1-6-r2-dipyrazolo[3,4-b:4′,3′-f][1,5]diazocine-5,10-diones of pharmaceutical interest
The non-selective methylation of compounds 3a-d using ethereal diazomethane, allowed the synthesis of isomers 4 and 5 which were useful intermediates for the preparation, by a simple approach, of the title compounds 7 and 9. A complete assignment of the chemical shifts to the carbon atoms of the compounds 7 and 9 was performed by different nmr experiments, such as DEPT and XHDEPT for onebond CH correlations and COLOC experiments for long-range C-H correlations.
ChemInform Abstract: Methylation of 2-Phenylamino-1,3,4-thiadiazole. A Structure Debated.
The true identity of the 4-methyl-5-phenylimino-δ2-1,3,4-thiadiazoline (A) has been demonstrated. The reactions, previously reported in the literature to give A have been repeated and the structure of the compounds obtained has been established.
Methylation of 2-phenylamino-1,3,4-thiadiazole. A structure debated
The true identity of the 4-methyl-5-phenylimino-δ2-1,3,4-thiadiazoline (A) has been demonstrated. The reactions, previously reported in the literature to give A have been repeated and the structure of the compounds obtained has been established.
ChemInform Abstract: Synthesis and Spectroscopic Characterizations of Both 1-Ethyl-4,8- dihydro-10-methoxy-3-methyl-8-R1-6-R2-dipyrazolo(3,4-b:4′,3′-f)(1,5) diazocin-5(1H)-ones and 1-Ethyl-1,4,8,9-tetrahydro-3,9-dimethyl-8-R1-6- R2-dipyrazolo(3,4-b:4′,3′-
The non-selective methylation of compounds 3a-d using ethereal diazomethane, allowed the synthesis of isomers 4 and 5 which were useful intermediates for the preparation, by a simple approach, of the title compounds 7 and 9. A complete assignment of the chemical shifts to the carbon atoms of the compounds 7 and 9 was performed by different nmr experiments, such as DEPT and XHDEPT for onebond CH correlations and COLOC experiments for long-range C-H correlations.