Karle, Isabella L.; Flippen-Anderson, Judith L.; Chiang, Joseph F.; Lowrey, Alfred H. published the artcile< The conformations of five tetra- and pentamethoxylated phenyl derivatives: Weberine analogs and polymethoprims>, HPLC of Formula: 82-73-5, the main research area is mol structure weberine analog polymethoprim; conformation weberine analog polymethoprim; tetramethoprim structure; pentamethoprim structure; methoxyisoquinoline structure.
The conformations of methoxy groups on Ph rings when there are 4 or more adjacent methoxy groups were established. In 3 of the compounds studied, the Me C atoms are placed alternately above and below the plane of the aryl group in a regular fashion, while in 2 very similar compounds there are unexpected irregularities in the rotations about the CPh-O bonds and consequent crowding of adjacent methoxy groups. Relative potential energy profiles calculated by the MM2 program for the rotation about CPh-O bonds in the free mols. do not provide any clues for the irregularities. The unexpected methoxy conformations appear to result from packing interactions. 5,6,7,8-Tetramethoxy-1,2-dimethyl-1,2,3,4-tetrahydroisoquinoline hydrochloride (1-methylweberine.HCl) is orthorhombic, space group Pbca, with a 10.262(4), b 17.865(4), and c 18.127(4) Å, d.(calculated) = 1.270 for Z = 8; R = 6.8% for 2009 reflections. 2-(2,3,4,5-Tetramethoxyphenyl)ethylamine hydrochloride is monoclinic, space group P21/a, with a 10.646(8), b 7.623(6), c 18.862(10) Å, and β 104.47(6)°; d.(calculated) = 1.244 for Z = 4; R = 7.7% for 1105 reflections. 5,6,7,8-Tetramethoxy-1-methylisoquinoline hydrochloride is triclinic, space group P1̅, with a 9.298(4), b 9.679(4), c 9.664(4) Å, α 80.77(3), β 63.44(3), and γ 70.36(3)°; d.(calculated) = 1.359 for Z = 2; R = 4.9% for 1787 reflections. 2,4-Diamino-5-(2,3,4,5-tetramethoxybenzyl)pyrimidine (tetramethoprim) is monoclinic, space group P21/n, with a 12.335(10), b 11.828(10), c 12.511(10) Å, and β 119.00(6)°; d.(calculated) = 1.33 for Z = 4; R = 10.3% for 1075 reflections. 2,4-Diamino-5-(2,3,4,5,6-pentamethoxybenzyl)pyrimidine (pentamethoprim) is triclinic, space group P1̅, with a 6.016(4), b 8.319(5), c 18.613(10) Å, α 82.73(5), β 83.58(5), and γ 89.29(5)°; d.(calculated) = 1.267 for Z = 2; R = 8.6% for 1531 reflections. Rotations about the 2 bonds linking the aryl groups are similar in pentamethoprim and trimethoprim but quite different from tetramethoprim. Relative potential energies for both conformations are similar. Only trimethoprim exhibits potent antifolate activity.
Acta Crystallographica, Section B: Structural Science published new progress about Crystal structure. 82-73-5 belongs to class bromides-buliding-blocks, and the molecular formula is C8H3BrO3, HPLC of Formula: 82-73-5.
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary