REGIOISOMERIC N-ALKYLATION OF SOME INDAZOLES

Abstract

Objective: Indazole scaffold have two interconvertible tautomeric forms. Based on our previous studies, regioisomeric N-alkylation of some indazole analogs was synthesized in this study and their structures were elucidated by 2D NMR methods. Material and Method: Regioisomers were resolved for N-benzylations and alkylation of some non-substituted and substituted indazoles, under basic conditions (K2CO3) in DMF. Result and Discussion: It was observed that, their occurrence ratios of N1 : N2 is almost equal (50%). Their structures were established by combination of 1H-1H NOE (Nuclear Overhauser Effect Spectroscopy, NOESY) and HMBC (Heteronuclear Multiple Bond Correlation) NMR methods.

Keywords

• HMBC
• indazole (1,2-benzodiazole)
• NOESY
• regioisomers

Thanks

Central Laboratory of Pharmacy, Faculty of Ankara University provided support for acquisition of NMR and mass spectrometer used in this work.

BAZI İNDAZOLLERİN REGİOİZOMERİK N-ALKİLASYONU

Abstract

Amaç: İndazol halkası iki tautomerik forma sahiptir. Önceki çalışmalarımızda yola çıkarak, bu çalışmada bazı indazol analoglarının regioizomerik N-alkilasyonu sentezlendi ve yapıları 2D NMR yöntemleriyle aydınlatıldı. Gereç ve Yöntem: Bazı non-sübstitüe ve sübstitüe indazollerin, DMF içinde bazik koşullar (K2CO3) altında N-alkilasyonu yoluyla regioizomerik N-alkilasyon türevleri elde edildi. Sonuç ve Tartışma: N1 : N2 oluşum oranlarının neredeyse eşit olduğu (%50) gözlemlendi. Moleküllerin yapıları, 1H-1H NOE (Nuclear Overhauser Effect Spectroscopy, NOESY) ve HMBC (Heteronuclear Multiple Bond Correlation) NMR yöntemleri ile aydınlatıldı.

Keywords

• HMBC
• indazol (1,2-benzodiazol)
• NOESY
• regioizomer

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