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Cisplatin is an extremely effective cancer chemotherapeutic agent, but its use is often accompanied by toxicity. Second generation drugs such as carboplatin are becoming more widely used because of reduced toxicity. Since biotransformation products have been implicated in the toxic responses, we have begun to investigate the reactions of cisplatin and carboplatin with potential biological ligands. Reaction products were characterized using HPLC with inductively coupled plasma - mass spectrometry (HPLC-ICP-MS), H1 and C13 NMR and fast atom bombardment - mass spectrometry (FAB-MS). Three Pt-creatinine complexes, cis-[Pt(NH3)2Cl(Creat)]+, cis-[Pt(NH3)2(H2O)(Creat)]2+ and cis-[Pt(NH3)2(Creat)2]2+, were synthesized and the platinum was shown to coordinate to the ring nitrogen, N(3). Human urine samples from patients on cisplatin chemotherapy were shown to contain cisplatin, its hydrolysis product and biotransformation products containing Pt-creatinine, Pt-urea and Pt-uric acid complexes. Urine from carboplatin patients shows fewer biotransformation products. Studies with control and diabetic (protected against cisplatin toxicity) rats showed systematic differences in the biotransformation products formed on administration of cisplatin.

The microwave oven synthesis of a sterically congested macrocycle 6,8,15,17-tetraphenyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinato nickel(II), abbreviated [Ni(Ph4Bzo2[14]tetraeneN4)], is presented as an advanced inorganic chemistry laboratory. The template reaction is done in a commercial microwave oven and the reaction is complete in about 20 minutes. After chromatography and recrystallization, a sufficient amount of macrocycle (50-100 mg) for IR, NMR, UV-vis, or electrochemical studies is obtained. The experiment can be completed within the time-span of most laboratory classes and the yield from microwave synthesis is comparable to that of the published method which requires more extreme reaction conditions. [Ni(Ph4Bzo2[14]tetraeneN4)] is an attractive macrocycle for study because of its stability and solubility in organic solvents. The 1H and 13C NMR spectra illustrate the high symmetry of this compound and the signals are easily assigned. The electronic spectrum shows five major absorptions and this complex is an excellent substrate for electrochemical analysis because it does not electropolymerize on the electrode surface.

The synthesis of the title compound by a three-step procedure is described. The hydrolysis kinetics, which involve two consecutive psuedo-first-order processes, are also described. The synthesis and kinetics experiments described here are proposed for incorporation into undergraduate laboratory courses under a variety of formats. The compound described here is related to a toxic metabolite of the common analgesics acetaminophen and phenacetin.

This article describes a procedure for the purification of an enzyme from a readily available animal tissue. It allows for classical methods of enzyme purification to be examined by students. These methods include homogenization, centrifugation, isoelectric precipitation, and affinity chromatography. The experimental procedure is straightforward and most equipment is available at even small colleges and universities. Most teaching methods of protein isolation do not include an affinity chromatography step and the experiment benefits from the inclusion of this technique into the protocol.