Crystal structure of two brom containing aza-tetracyclic fused-ring N-heterocycles including isoxazolidine ring

Abstract

Crystal structure of two brom containing aza-tetracyclic fused N-heterocycles including isoxazolidine ring compounds have been determined in single-crystal X-ray diffraction studies. The compound, C14H19BrN2O3, (1), and C12H15BrN2O3, (2), were obtained from a stereospecific[3+2] 1,3-cycloaddition of oxime based tandem nitrone generation reactions. The envelope conformation of the isoxazolidine rings are different, leading the substituents to be pseudoaxial in (1) and pseudoequatorial in (2). The stereochemistry of these fused compounds are exo- and endo-stereoisomer geometry contributed by exo and endo transition state of nitrone 1,3-dipolar cycloaddition reactions. The title compound (1) crystallizes in the monoclinic space group P2 1/n with a = 12.6221(5)A, b = 7.5917(4) A, c = 16.2350(9) A, β = 112.254(5)°, V = 1439.81(12) A3, and D calc = 1.583 Mg/m3 for Z = 4 and compound (2) crystallizes in the monoclinic space group P2 1/c with a = 11.6906(9) A, b = 6.4255(7) A, c = 17.2070(10) A, β = 109.264(5)°, V = 1220.2(2) A3, and D calc = 1.716 Mg/m3 for Z = 4. The antibacterial activity of both compounds were investigated for three Gram (+) and two Gram (−) bacteria by employing broth microdilution method and subsequently inhibitory activity against yeast-like fungi was also determined.