INVESTIGADORES
ORELLI Liliana Raquel
congresos y reuniones científicas
Título:
1H AND 13C NMR STUDY OF 5-ARYLPYRIMIDOQUINOXALINE N-OXIDES AND RELATED COMPOUNDS
Autor/es:
NADIA GRUBER; MA. BEATRIZ GARCÍA; LILIANA R. ORELLI
Lugar:
Aveiro
Reunión:
Congreso; IV Iberoamerican NMR Meeting; 2012
Institución organizadora:
Sociedad Química de Portugal
Resumen:
1H AND 13C NMR STUDY OF 5-ARYLPYRIMIDOQUINOXALINE N-OXIDES AND RELATED COMPOUNDSNadia Gruber, Ma. Beatriz García, Liliana R. Orelli Departamento de Química Orgánica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina.ngruber@ffyb.uba.arAmidinoquinoxaline N-oxides have received attention due to their pharmacological properties, acting as antibacterials, antiamoebics and antineoplastics. As part of our research on nitrogen heterocycles, we recently developed a novel procedure for the synthesis of 5-aryl (and alkyl)-2,3-dihydropyrimidoquinoxaline 6-oxides and investigated their chemical and biological properties. We present here the complete 1H and 13C NMR assignment of a series of 2,3-dihydro-1H-pyrimido[1,2-a]quinoxaline 6-oxides 1 by means of 1D and 2D NMR techniques, including HMQC and HMBC experiments. The compounds were prepared using the synthetic procedure reported by our group. Two novel derivates are included, which show modifications in the fused benzene ring (X=N) and the 5-aryl substituent (Ar=2-thienyl).In order to investigate the effect of N-deoxygenation and quaternization of the parent heterocycle, the spectra of componds 2,3 were unambiguous assigned. We also discuss the results obtained by computational methods, which suggest the presence of a ?weak hydrogen bond? between the oxygen and the hydrogen peri to the N-oxide group in componds 1 and 3.1. Among others: G. J. Ellames, K. R. Lawson, A. A. Jaxa-Chamiec and R. M. Upton, 1988, EP 0,256,545. 2. M. B. García, L. R. Orelli, M. L. Magri, I. A. Perillo. Synthesis, 2002, 18, 2687-2690.3.M. B. García, L. R. Orelli and I. A. Perillo, J. Heterocycl. Chem., 2006, 43, 1703-1707.4. M. L. Lavaggi, G. Aguirre, L. Boiani, L. Orelli, B. García, H. Cerecetto, M. González, Eur. J. Med. Chem., 2008, 43, 1737-1741.
