Aqua-bis(1H-benzimidazole-2-carboxyl-ato-κO,N)zinc(II).

In the title compound, [Zn(C(8)H(5)N(2)O(2))(2)(H(2)O)], the Zn(II) ion is coordinated in each case by a carboxyl-ate O atom and an imidazole N atom from two different benzimidazole-2-carboxyl-ate (BIC) ligands and one water O atom in a trigonal-bipyramidal geometry. In the complex mol-ecule, the two benzimidazole planes are twisted, making a dihedral angle of 55.93 (11)°. The three-dimensional framework is organized by inter-molecular N-H⋯O hydrogen bonding and O-H⋯O inter-actions and π-π inter-actions between adjacent benzimidazole rings [centroid-centroid distance = 3.586 (3) Å].

(N-{[4-(1,3-benzothiazol-2-yl)anilino]carbonylmethyl-kappaO}iminodiacetato-kappa(3)O,N,O')(1,10-phenanthroline-kappa(2)N,N')cobalt(II) pentahydrate.

The title compound, [Co(C(19)H(15)N(3)O(5)S)(C(12)H(8)N(2))] x 5 H(2)O, has a moderately distorted octahedral coordination environment composed of two N atoms of a 1,10-phenanthroline ligand and one N and three O atoms of an N-{[4-(1,3-benzothiazol-2-yl)anilino]carbonylmethyl}iminodiacetate (ZL-5(2-)) ligand. The ring systems of the phenanthroline and ZL-5(2-) ligands are coplanar and the complexes pack in layers parallel to the ab plane with the rings of adjacent complexes facing one another. The layers stack along the c axis and are linked by hydrogen bonds involving the five water solvent molecules in the asymmetric unit and O atoms of the acetate groups of the ZL-5(2-) ligand. This is believed to be the first crystal structure of a complex of a 2-(4-aminophenyl)benzothiazole ligand.

[Treatment of second primary malignant tumor induced by radiotherapy].

OBJECTIVE: To study the diagnosis and treatment of a second primary malignant tumor induced by previous radiotherapy. METHODS: From March 1970 to March 1997, 108 nasopharyngeal cancer (NPC) patients who developed a second primary malignant tumor induced by radiotherapy were treated. There were squamous carcinoma 43 (39.8%), sarcoma 26 (24.1%), malignant fibrous histiocytoma 14 (13.0%), adenoid cystic carcinoma 12 (11.1%), thyroid papillary adenocarcinoma 8 (7.4%) and malignant melanoma 5 (4.6%). Fifty patients underwent operation, 32 received radiotherapy, 18 received chemotherapy and 8 received operation combined with chemotherapy. RESULTS: The 3- and 5-year tumor-free survival rates were 64.0% and 36.0% in the operation group. They were 34.4% and 18.8% in the radiotherapy group. CONCLUSION: Surgery, if not contra-indicated, is the first choice for the second primary malignant tumor induced by radiotherapy. Aggressive treatment for these patients is, hence, indicated clinically.