Crystal structure of bis-[cis-(1,4,8,11-tetra-aza-cyclo-tetra-deca-ne-κ4N)bis(thio-cyanato-κN)chrom-ium(III)] dichromate monohydrate from synchrotron X-ray diffraction data.

The structure of the complex salt, cis-[Cr(NCS)2(cyclam)]2[Cr2O7]·H2O (cyclam = 1,4,8,11-tetra-aza-cyclo-tetra-decane, C10H24N4), has been determined from synchrotron data. The asymmetric unit comprises of one [Cr(NCS)2(cyclam)]+ cation, one half of a Cr2O72- anion (completed by inversion symmetry) and one half of a water mol-ecule (completed by twofold rotation symmetry). The CrIII ion is coordinated by the four cyclam N atoms and by two N atoms of cis-arranged thio-cyanate anions, displaying a distorted octa-hedral coordination sphere. The Cr-N(cyclam) bond lengths are in the range 2.080 (2) to 2.097 (2) Šwhile the average Cr-N(NCS) bond length is 1.985 (4) Å. The macrocyclic cyclam moiety adopts the cis-V conformation. The bridging O atom of the dichromate anion is disordered around an inversion centre, leading to a bending of the Cr-O-Cr bridging angle [157.7 (3)°]; the anion has a staggered conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups and water O-H groups as donor groups, and the O atoms of the Cr2O72- anion and water mol-ecules as acceptor groups, giving rise to a three-dimensional network.

Phase III long-term study and comparative clinical study of nipradilol ophthalmic solution in patients with primary open-angle glaucoma and ocular hypertension.

Nipradilol (CAS 81486-22-8) is a non-selective beta-blocker with alpha-1 blocking and nitroglycerin-like vasodilating activities. In the present communication, the long-term efficacy and safety of nipradilol were investigated and the efficacy, safety and utility of topical nipradilol and timolol (CAS 91524-16-2) were compared in patients with primary open-angle glaucoma or ocular hypertension. In the long-term study, nipradilol for 1 year (52 weeks) was performed by registration method. 67 out of 68 patients were subjected to analysis and 57 patients (83.8 %) completed 52-week instillation. 0.25 % nipradilol was applied twice daily to patients. As a result, intraocular pressure (IOP) decreased significantly by 4.0 mmHg to 4.8 mmHg compared with the baseline without tachyphylaxis. The incidence of adverse events was 12.5 % at 52 weeks by analysis with Kaplan-Meier life-table method. It showed no significant trend of increase after 3 months. In the multi-centered double-masked comparative randomized study, 0.25 % nipradilol was assigned to 96 patients and 0.5 % timolol to 100 patients. Each patient was instilled nipradilol or timolol twice daily for 8 weeks. IOP significantly decreased by 4.2 mmHg and by 4.7 mmHg at 8 weeks and the incidence of adverse events was 10.5 % and 12.1 % in the nipradilol and timolol group, respectively. No significant between-group difference in IOP reduction or incidence of adverse events was seen. Topical nipradilol showed long-term ocular hypotensive effects and clinical safety in a 52-week study, and its efficacy and safety equivalent to timolol was confirmed in a 8-week comparative study.