Synthesis, Characterization And Structural Studies Of Medicinally Important Pyridine Derivatives

• Main Author: Farhadikoutenaei, Abbas
• Format: Thesis
• Language: English
• Published: 2016
• Subjects: QC1 Physics (General)
• Online Access: http://eprints.usm.my/31550/1/ABBAS_FARHADIKOUTENAEI_24.pdf; http://eprints.usm.my/31550/

Dalam kajian ini, dua puluh garam 2-amino-5-metilpiridin dan 2-amino-4-metilpirimidin dengan asid karboksilik aromatik dan alifatik asli telah dikaji menggunakan kaedah spektroskopik seperti: kristalografi sinar-X serbuk dan hablur tunggal, spektroskopi inframerah (IR) dan resonan magnet nuklear (NMR). Dalam semua sebatian, N yang diprotonkan dan kumpulan 2-amino kation terikat dengan ikatan hidrogen kepada atom O karboksilat anion melalui sepasang ikatan hydrogen N‒H···O dan N+‒H···O¯, membentuk motif gelang R 2/2 (8). Penghalusan struktur menunjukkan yang empat belas dari sebatian menghablur dalam kumpulan ruang monoklinik, empat dalam triklinik dan setiap satu dalam tetragonal dan ortorombik. Dalam kajian ini, pembentukan hablur ditunjukkan oleh persetujuan yang baik antara corak belauan serbuk sampel dan corak simulasi dari data belauan hablur tunggal dan kedua-duanya berbeza dari corak serbuk bahan awal. In this work, twenty novel salts of 2-amino-5-methylpyridine and 2-amino-4-methylpyrimidine with aromatic and aliphatic carboxylic acids have been investigated using spectroscopic methods such as powder and single crystal X-ray crystallography, infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. In all the compounds, the protonated N atom and the 2-amino group of the cations are hydrogen bonded to the carboxylate O atoms of the anions via a pair of N‒H···O and N+‒H···O¯ hydrogen bonds, forming an R 2/2 (8) ring motifs. The refinement of the structures indicates that fourteen of the compounds crystallized in the monoclinic space group, four in triclinic and one each in tetragonal and orthorhombic. In this research, the formation of the new crystal is shown by a good consistency between the powder diffraction pattern of the bulk samples and the simulated patterns obtained from single X-ray diffraction data and they were different from the powder pattern of the starting materials.