Selective hydroboration of dieneamines. Formation of hydroxyalkylphenothiazines as MDR modulators
摘要:
N-dienylphenothiazines synthesized from tetrazolo[1,5-a]pyridinium salts by treatment with phenothiazine were subjected to catalytic hydrogenation to yield N-butylphenothiazines, whereas transformation of these dienes with borane dimethyl sulfide (BH3 x Me2S) resulted in selective hydroboration of one double bond and full reduction of the other double bond to give 2-hydroxybutylphenothiazines. Position of the hydroxyl group was supported by NMR spectroscopy and verified by X-ray analysis. Comparison of MDR modulatory activity of the new derivatives revealed that the hydroxybutyl compounds are promising candidates for development of novel MDR inhibitors. (C) 2012 Elsevier Ltd. All rights reserved.
N-dienylphenothiazines synthesized from tetrazolo[1,5-a]pyridinium salts by treatment with phenothiazine were subjected to catalytic hydrogenation to yield N-butylphenothiazines, whereas transformation of these dienes with borane dimethyl sulfide (BH3 x Me2S) resulted in selective hydroboration of one double bond and full reduction of the other double bond to give 2-hydroxybutylphenothiazines. Position of the hydroxyl group was supported by NMR spectroscopy and verified by X-ray analysis. Comparison of MDR modulatory activity of the new derivatives revealed that the hydroxybutyl compounds are promising candidates for development of novel MDR inhibitors. (C) 2012 Elsevier Ltd. All rights reserved.