Analyses structurales et spectrales comparées du 5H-pyrazolo[3,4-d]pyrimidine-4-thione (tisopurine) et de sa forme protonée, le chlorure de 4-thioxo-2,5H,7H+-pyrazolo[3,4-d]pyrimidinium à l’état cristallin
✍ Scribed by E. Perez-Ruiz; J. L. Delarbre; L. Maury; M. Selkti; A. Tomas
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 365 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0377-0486
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✦ Synopsis
The molecular structure of the protonated form of tisopurine, 4-thioxo-2,5H,7H '-pyrazolo [ 3,4-d ] pyrimidinium chloride, (TPH'Cl-), was determined by x-ray di †raction methods. The crystals are monoclinic, C 5 H 5 N 4 SCl space group with a = 7.332(5), b = 10.911(9) and c = 9.423(8) b = 104.99(6)Ä, V = 728(2) and P2 1 /a, A , A 3 Z = 4. The structure was reÐned to R = 0.043. TPH'Cl-was found to be in the thione form with hydrogen atoms bonded to the N-1, N-3 and N-8 atoms. A comparison between tisopurine base in the monoclinic form (form I) and the chloride (TPH'Cl-) is proposed. The Raman and infrared spectra of the crystalline powders of the tisopurine bases [ monoclinic (form I) and orthorhombic (form II) ] and deuterated (TD) and chloride (TPH'Cl-) forms were investigated from 4600 to 20 cm-1. The two polymorphic base forms of the tisopurine were identiÐed by spectral analysis. The assignments of the fundamental vibrations involved in intermolecular H-bonds as NÈH(D)AE AE AEN and N'ÈH(D)AE AE AEClare discussed. 1998 John Wiley & Sons, Ltd. ( La structure mole culaire de la forme protone e de la tisopurine, le chlorure de 4-thioxo-2,5H,7H-pyrazolo[3,4d]pyrimidinium, (TPHCl~), a e te de termine e par di †raction des rayons X. Les cristaux appar-C 5 H 5 N 4 SCl tiennent au groupe dÏespace monoclinique avec a \ 7.332(5), b \ 10.911(9) et c \ 9.423(8) P2 1 /a, Ó, b \ 104.99(6)¡, V \ 728(2) et Z \ 4. La structure ae te affine e jusquÏaun facteur R \ 0.043. Le TPHCl~se Ó3 trouve sous la forme thione avec les atomes dÏhydrogene lie s aux atomes N-1, N-3 et N-8. Une comparaison entre la tisopurine base, sous sa forme monoclinique (forme I), et son chlorure (TPHCl~), est propose e. Les spectres Raman et infrarouge des poudres cristallines de la tisopurine sous ses formes bases [monoclinique (forme I) et orthorhombique (forme II)] deuterie e (TD) et chlorure (TPHCl~) ont e te analyse s de 4600 a20 cm~1. Les deux formes polymorphes de la tisopurine base ont e te identiÐe es par lÏanalyse spectrale. LÏattribution des principaux modes de vibration implique s dans les liaisons hydrogene intermole culaires de type NÈH(D)É É ÉN et N`ÈH(D)É É ÉCl~est discute e.