Browsing by Author "Yeap, C.S."

Now showing 1 - 18 of 18

2-(4-Bromo-phen-yl)-2-oxoethyl 4-chloro-benzoate
(2011) Fun, H.-K.; Yeap, C.S.; Garudachari, B.; Isloor, A.M.; Satyanarayan, M.N.
The asymmetric unit of the title compound, C 15H 10BrClO 3, consists of three crystallographically independent mol-ecules. The dihedral angles between the benzene rings in the three mol-ecules are 68.8 (2), 0.7 (3) and 66.1 (2) . In the crystal, the three independent mol-ecules are inter-connected by C - H?O hydrogen bonds, leading to isolated trimers. Fun et al. 2011.
2-(4-Bromo-phen-yl)-2-oxoethyl 4-chloro-benzoate
(2011) Fun, H.-K.; Yeap, C.S.; Garudachari, B.; Isloor, A.M.; Satyanarayan, M.N.
The asymmetric unit of the title compound, C 15H 10BrClO 3, consists of three crystallographically independent mol-ecules. The dihedral angles between the benzene rings in the three mol-ecules are 68.8 (2), 0.7 (3) and 66.1 (2)°. In the crystal, the three independent mol-ecules are inter-connected by C - H?O hydrogen bonds, leading to isolated trimers. © Fun et al. 2011.
2-(4-Methylanilino)acetohydrazide
(2009) Fun, H.-K.; Yeap, C.S.; Malladi, S.; Padaki, M.; Isloor, A.M.
In the title mol-ecule, C9H13N9O, the non-hydrogen atoms of the hydrazide group are essentially planar [maximum deviation = 0.028 (1) for one of the N atoms]. The mean plane of this group forms a dihedral angle of 83.34 (5) with the plane of the benzene ring. In the crystal structure, molecules are linked by inter-molecular N - H?O, N - H?N and weak C - H?N hydrogen bonds into a two-dimensional network parallel to the ab plane. Additional stabilization is provided by a weak C - H?? inter-action. Fun et al. 2009.
2-(4-Methylanilino)acetohydrazide
(2009) Fun, H.-K.; Yeap, C.S.; Malladi, S.; Padaki, M.; Isloor, A.M.
In the title mol-ecule, C9H13N9O, the non-hydrogen atoms of the hydrazide group are essentially planar [maximum deviation = 0.028 (1) Å for one of the N atoms]. The mean plane of this group forms a dihedral angle of 83.34 (5)° with the plane of the benzene ring. In the crystal structure, molecules are linked by inter-molecular N - H?O, N - H?N and weak C - H?N hydrogen bonds into a two-dimensional network parallel to the ab plane. Additional stabilization is provided by a weak C - H?? inter-action. © Fun et al. 2009.
2-Dibutylamino-1-(2,7-dichloro-9H-fluoren-4-yl)ethanol
(2010) Fun, H.-K.; Yeap, C.S.; Vijesh, A.M.; Isloor, A.M.; Vasudeva, P.K.
In the title compound, C23H29Cl2NO, the fluorene ring is essentially planar, with a maximum deviation from the mean plane of 0.041 (1) . The amine group adopts a pyramidal configuration, the sum of the bond angles being 336.2 (3) . In the crystal, the molecules are linked into dimers by inter-molecular O - H?N and C - H?O hydrogen bonds. Weak C - H?? and ?-? [centroid-centroid distance = 3.7544 (7) ] interactions are also observed.
2-Dibutylamino-1-(2,7-dichloro-9H-fluoren-4-yl)ethanol
(2010) Fun, H.-K.; Yeap, C.S.; Vijesh, A.M.; Isloor, A.M.; Vasudeva, P.K.
In the title compound, C23H29Cl2NO, the fluorene ring is essentially planar, with a maximum deviation from the mean plane of 0.041 (1) Å. The amine group adopts a pyramidal configuration, the sum of the bond angles being 336.2 (3)°. In the crystal, the molecules are linked into dimers by inter-molecular O - H?N and C - H?O hydrogen bonds. Weak C - H?? and ?-? [centroid-centroid distance = 3.7544 (7) Å] interactions are also observed.
4,6-Dimethoxy-2-(methylsulfonyl)pyrimidine
(2010) Fun, H.-K.; Yeap, C.S.; Rai, S.; Isloor, A.M.; Shetty, P.
The asymmetric unit of the title compound, C7H 10N2O4S, comprises of two independent mol-ecules (A and B) which differ in the orientation of the methyl-sulfonyl group [C - S - C - N = 157.98 (13) in mol-ecule A and 6.09 (18) in mol-ecule B]. In the crystal structure, mol-ecules of type A are linked into chains along the a axis by inter-molecular C - H?O hydrogen bonds. The B mol-ecules are linked to these chains by C - H?O hydrogen bonds.
4,6-Dimethoxy-2-(methylsulfonyl)pyrimidine
(2010) Fun, H.-K.; Yeap, C.S.; Rai, S.; Isloor, A.M.; Shetty, P.
The asymmetric unit of the title compound, C7H 10N2O4S, comprises of two independent mol-ecules (A and B) which differ in the orientation of the methyl-sulfonyl group [C - S - C - N = 157.98 (13)° in mol-ecule A and 6.09 (18)° in mol-ecule B]. In the crystal structure, mol-ecules of type A are linked into chains along the a axis by inter-molecular C - H?O hydrogen bonds. The B mol-ecules are linked to these chains by C - H?O hydrogen bonds.
4-Amino-3-[(4-methoxyphenyl)aminometh-yl]-1H-1,2,4-triazole-5(4H)-thione
(2009) Fun, H.-K.; Yeap, C.S.; Malladi, S.; Padaki, M.; Isloor, A.M.
The mol-ecule of the title compound, C10H13N 5OS, is approximately planar, the dihedral angle between the triazole and benzene rings being 4.53 (10) . The amino group adopts a pyramidal configuration. In the crystal structure, molecules are linked into two-dimensional networks parallel to (001) by inter-molecular N - H?S and N - H?N hydrogen bonds. In addition, an S?S short contact of 3.3435 (7) is observed. Fun et al. 2009.
4-Amino-3-[(4-methoxyphenyl)aminometh-yl]-1H-1,2,4-triazole-5(4H)-thione
(2009) Fun, H.-K.; Yeap, C.S.; Malladi, S.; Padaki, M.; Isloor, A.M.
The mol-ecule of the title compound, C10H13N 5OS, is approximately planar, the dihedral angle between the triazole and benzene rings being 4.53 (10)°. The amino group adopts a pyramidal configuration. In the crystal structure, molecules are linked into two-dimensional networks parallel to (001) by inter-molecular N - H?S and N - H?N hydrogen bonds. In addition, an S?S short contact of 3.3435 (7) Å is observed. © Fun et al. 2009.
(E)-1-(4-Fluoro-phen-yl)ethan-1-one semicarbazone
(2009) Fun, H.-K.; Yeap, C.S.; Padaki, M.; Malladi, S.; Isloor, A.M.
In the title compound, C9H10FN3O, the semicarbazone group is nearly planar, with the maximum deviation of 0.044 (1) for one of the N atoms. The mean plane of semicarbazone group forms a dihedral angle of 30.94 (4) with the benzene ring. The mol-ecules are linked into a supra-molecular chain by N - H?O hydrogen bonds formed along the c axis. The crystal structure is further stabilized by weak inter-molucular C - H?? inter-actions; the closest C?Cg contact is 3.6505 (11) .
(E)-1-(4-Fluoro-phen-yl)ethan-1-one semicarbazone
(2009) Fun, H.-K.; Yeap, C.S.; Padaki, M.; Malladi, S.; Isloor, A.M.
In the title compound, C9H10FN3O, the semicarbazone group is nearly planar, with the maximum deviation of 0.044 (1) Å for one of the N atoms. The mean plane of semicarbazone group forms a dihedral angle of 30.94 (4)° with the benzene ring. The mol-ecules are linked into a supra-molecular chain by N - H?O hydrogen bonds formed along the c axis. The crystal structure is further stabilized by weak inter-molucular C - H?? inter-actions; the closest C?Cg contact is 3.6505 (11) Å.
(E)-1-Phenyl-ethanone semicarbazone
(2009) Fun, H.-K.; Yeap, C.S.; Padaki, M.; Malladi, S.; Isloor, A.M.
In the title compound, C9H11N3O, the benzene ring is disordered over two positions with refined occupancies of 0.922 (5) and 0.078 (5). The program PLATON [Spek (2009). Acta Cryst. D65, 148-155] recommends the solution in the space group C2/m with a = 7.3050 (3), b = 6.6745 (2), c = 18.3853 (6) and ? = 96.986 (2) . However, the large number of non-extinct reflections needed to be ignored if C2/m is chosen suggested that the space group is incorrect, even though the R values are lower than that for P21/c. The semicarbazone group is essentially planar, with a maximum deviation of 0.046 (1) for one of the N atoms. The mean plane of the semicarbazone group forms dihedral angles of 33.61 (8) and 39.1 (9) with the benzene ring of the major and minor components, respectively. In the crystal structure, mol-ecules are linked by inter-molecular N - H?O hydrogen bonds into extended chains along the c axis. The crystal structure is further stabilized by weak inter-molucular C - H?? inter-actions. 2009 Fun et al.
(E)-1-Phenyl-ethanone semicarbazone
(2009) Fun, H.-K.; Yeap, C.S.; Padaki, M.; Malladi, S.; Isloor, A.M.
In the title compound, C9H11N3O, the benzene ring is disordered over two positions with refined occupancies of 0.922 (5) and 0.078 (5). The program PLATON [Spek (2009). Acta Cryst. D65, 148-155] recommends the solution in the space group C2/m with a = 7.3050 (3), b = 6.6745 (2), c = 18.3853 (6) Å and ? = 96.986 (2)°. However, the large number of non-extinct reflections needed to be ignored if C2/m is chosen suggested that the space group is incorrect, even though the R values are lower than that for P21/c. The semicarbazone group is essentially planar, with a maximum deviation of 0.046 (1) Å for one of the N atoms. The mean plane of the semicarbazone group forms dihedral angles of 33.61 (8) and 39.1 (9)° with the benzene ring of the major and minor components, respectively. In the crystal structure, mol-ecules are linked by inter-molecular N - H?O hydrogen bonds into extended chains along the c axis. The crystal structure is further stabilized by weak inter-molucular C - H?? inter-actions. © 2009 Fun et al.
(E)-2-(4-Hy-droxy-3-meth-oxy-benzyl-idene)hydrazinecarboxamide
(2011) Fun, H.-K.; Yeap, C.S.; Malladi, S.; Isloor, A.M.
The asymmetric unit of the title compound, C 9H 11N 3O3, consists of two crystallographically independent mol-ecules. Both mol-ecules are almost planar, with r.m.s. deviations of 0.107 and 0.099 . In the crystal, the two independent mol-ecules form a dimer with an R 2 2(8) ring motif via N - H?O hydrogen bonds. The dimers are further linked into a three-dimensional network by O - H?O and N - H?O hydrogen bonds. Fun et al. 2011.
(E)-2-(4-Hy-droxy-3-meth-oxy-benzyl-idene)hydrazinecarboxamide
(2011) Fun, H.-K.; Yeap, C.S.; Malladi, S.; Isloor, A.M.
The asymmetric unit of the title compound, C 9H 11N 3O3, consists of two crystallographically independent mol-ecules. Both mol-ecules are almost planar, with r.m.s. deviations of 0.107 and 0.099 Å. In the crystal, the two independent mol-ecules form a dimer with an R 2 2(8) ring motif via N - H?O hydrogen bonds. The dimers are further linked into a three-dimensional network by O - H?O and N - H?O hydrogen bonds. © Fun et al. 2011.
N-[(4-Amino-5-sulfanylidene-4,5-dihydro-1H-1,2,4-triazol-3-yl)methyl] -4-methylbenzamide
(2010) Fun, H.-K.; Yeap, C.S.; Mange, Y.; Isloor, A.M.; Hegde, C.
In the title compound, C11H13N5OS, the dihedral angle between the triazole ring and the benzene ring is 84.21 (7) . The amino group adopts a pyramidal configuration. An intra-molecular N - H?O hydrogen bond stabilizes the molecular structure and generates an S(8) ring. In the crystal, molecules are linked by inter-molecular N - H?O, N - H?S, N - H?N and C - H?S hydrogen bonds into layers lying parallel to the bc plane. The crystal structure is further stabilized by aromatic ?-? stacking interactions [centroid-centroid distance = 3.3330 (7) ].
N-[(4-Amino-5-sulfanylidene-4,5-dihydro-1H-1,2,4-triazol-3-yl)methyl] -4-methylbenzamide
(2010) Fun, H.-K.; Yeap, C.S.; Mange, Y.; Isloor, A.M.; Hegde, C.
In the title compound, C11H13N5OS, the dihedral angle between the triazole ring and the benzene ring is 84.21 (7)°. The amino group adopts a pyramidal configuration. An intra-molecular N - H?O hydrogen bond stabilizes the molecular structure and generates an S(8) ring. In the crystal, molecules are linked by inter-molecular N - H?O, N - H?S, N - H?N and C - H?S hydrogen bonds into layers lying parallel to the bc plane. The crystal structure is further stabilized by aromatic ?-? stacking interactions [centroid-centroid distance = 3.3330 (7) Å].