کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1790707 | 1524445 | 2013 | 9 صفحه PDF | دانلود رایگان |

• 3β-Chloro-5α,6α-epoxycholestane and 3β-acetoxy-5α,6α-epoxycholestane have been synthesized from m-CPBA.
• Structural assignment has been performed on the basis of FT-IR, FT-Raman, 1H NMR, 13C NMR, 2D COZY, NOESY, UV–visible and X-ray crystallography.
• The two crystals (1 and 2) belong to Sohncke space groups P212121 (Z=8) and P21 (Z=4) respectively.
• Thermal studies (TG–DTA–DSC) showed thermal stability and good crystalinity of the compounds.
α-Selective epoxidation of 3β-chlorocholest-5-ene and 3β-acetoxycholest-5-ene has been performed with m-CPBA to synthesize 3β-chloro-5α,6α-epoxycholestane (1) and 3β-acetoxy-5α,6α-epoxycholestane (2). We provided an analysis of these compounds by means of FT-IR, FT-Raman, 1H NMR, 13C NMR, 2D cosy, NOESY, UV–visible and X-ray crystallography. The compound 1 crystallizes in the orthorhombic space group P212121 while compound 2 crystallizes in the monoclinic space group P21. We compared the conformations of both compounds in solid state and in solution by calculation of dihedral angles and coupling constant values. The powder X-ray diffraction (PXRD) of the compound was recorded to ascertain the purity of the grown crystals. Thermogravimetric analysis showed stability of the compounds up to 250 °C. Moreover, the ICH rule has been applied to test the stability of two crystals, which showed significant stability.
Journal: Journal of Crystal Growth - Volume 384, 1 December 2013, Pages 135–143