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Phosphorus-nitrogen compounds. 20. Thiophosphorus hydrazones.

Six pyridine-2-carboxaldehyde, one pyridine N-oxide 2-carboxaldehyde, and five diketone thiophosphoric hydrazones, three thiophosphoric hydrazides, and two cupric chelates were synthesized. The chelates and nine of the hydrazones were tested against Ehrlich ascites carcinoma. Seven of these latter agents were administered concurrently with either cupric and/or ferrous salts to mice bearing this tumor. The greatest activity was found with the chelate, cimethyl pyridine-2-carboxyaldehyde phosphorothioic hydrazone-copper (1:1). The hydrazone portion of this chelate also formed a ligand-copper (2:1) complex. Although all of the hydrazones but one were inactive when evaluated alone, the concurrent injection of cupric ion increased survival times by an avoli alkaline phosphatase was found to be inhibited by two thiosemicarbazones in a manner similar to that previously reported by these agents against alkaline phosphatase derived from Sarcoma 180-6-thiopurine resistant ascites cells. None of the 14 hydrazides or hydrazones tested against E. coli enzyme displayed significant inhibition.

Alkaline Phosphatase↗

Phosphorus-nitrogen compounds. 26. Phosphaminimides. 2. 2,2'-Phosphinylidenebis(1,1,1-trimethylhydrazinium) iodide inner salts as agents affecting ganglionic transmission.

The N-2 atoms of phosphorus 2,2-dimethylhydrazides, contrary to a previous report, can be methylated by iodomethane. Treatment of the resulting dihydrazinium iodides with aqueous sodium hydroxide results in mono- instead of didehydroiodination, apparently due to resonance stabilization of the inner salt form. The phosphaminimide products and their hydrazinium iodide precursors blocked sympathetic ganglionic transmission while one dihydrazide intermediate produced potentiation. Brine shrimp testing indicated that conversion of a hydrazinium iodide to an aminimide moiety results in decreased toxicity.

Animals↗

Dative sigma- and pi-bonding in boron-nitrogen compounds: molecular structures of (CH3)2NB(CH3)N(CH3)B(CH3)2 and [(CH3)2B]2NN(CH3)2 determined by gas electron diffraction and quantum chemical calculations.

The molecular structures of dimethylamino[(dimethylboryl)methylamino]methylborane, Me2NBMeNMeBMe2 (1) and 1,1-bis(dimethylboryl)-2,2-dimethylhydrazine, (Me2B)2NNMe2 (2) have been determined by gas electron diffraction (GED), density functional theory calculations at the B3PW91/6-311++G** level and ab initio calculations at the MP2/6-311++G** level. 1 adopts an open structure similar to that of the isoelectronic hydrocarbon molecule permethylbutadiene; the central B-N bond distance at 148.0/149.3(7) pm (MP2/GED) corresponds to a single covalent N--B bond distance, the two terminal distances, 140.9/140.5(4) pm and 141.8/141.3(4) pm, correspond to the distance between N and B atoms joined by a covalent sigma-bond and a dative pi-bond. A closed form where the establishment of a dative bond between the terminal N and B atoms has led to the formation of a four-membered ring also corresponds to a minimum on the potential energy surface, but the energy is calculated to be 14.3 kJ mol(-1) higher at the MP2 level. This structure is also incompatible with the GED data. 2 adopts a structure in which a dative sigma-bond between the dimethylamino N atom and one of the boron atoms has led to the formation of a three-membered N(2)B ring. The dative sigma-bond distance is 165.5/164.0(13) pm, the two other bond distances in the ring are N-B=150.6/148.9(9) pm corresponding to a covalent sigma-bond and N-N=145.1/145.4(3) pm. The terminal B--N distance 139.6/138.9(9) pm is consistent with a covalent sigma-bond augmented by a dative pi-bond. An open Y-shaped structure also corresponds to a minimum on the potential energy surface, but the energy is 18.7 kJ mol(-1) higher (MP2) and it is incompatible with the GED data.

Journal Article↗