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PubMed2005

Three-dimensional nonlinear optical chromophores based on metal-to-ligand charge-transfer from ruthenium(II) or iron(II) centers.

In this article, we describe a series of new complex salts in which electron-rich transition-metal centers are coordinated to three electron-accepting N-methyl/aryl-2,2':4,4' ':4',4' ''-quaterpyridinium ligands. These complexes contain either Ru(II) or Fe(II) ions and have been characterized by using various techniques, including electronic absorption spectroscopy and cyclic voltammetry. Molecular quadratic nonlinear optical (NLO) responses beta have been determined by using hyper-Rayleigh scattering at 800 nm and also via Stark (electroabsorption) spectroscopic studies on the intense, visible d --> pi* metal-to-ligand charge-transfer bands. The latter experiments reveal that these putatively octupolar D(3) chromophores exhibit two substantial components of the beta tensor which are associated with transitions to dipolar excited states. Computations involving time-dependent density-functional theory and the finite field method serve to further illuminate the electronic structures and associated linear and NLO properties of the new chromophoric salts.

Iron↗
PubMed1976

8-chloro-(S)- and -(R)-10-((S)-and -(R)-3'-methylethylaminopyrrolidino)- 10,11-dihydrodibenzo(b,f)thiepins. Synthesis and pharmacological studies.

The synthesis for 8-chloro-(S)- and -(R)-10-[(S)- and -(R)-3'-methylethylaminopyrrolidino]-10,11-dihydrodibenzo[b,f]thiepins is presented. The absolute configuration at position 3' of the aminopyrrolidino side chain is known from synthesis and corresponds to the asymmetric carbon atom in (S)- or (R)-aspartic acid. The absolute configuration at C-10 of the dihydrodibenzo[b,f]thiepin ring system was deduced from ORD-CD analysis coupled with degradation of partially resolved (+)-8-chloro-10-amino-10,11-dihydrodibenzo[b,f]thiepin to (+)-(S)-1,2-diphenylethylamine. The four isomers were studied in mice for their ability to block conditioned avoidance responding, antagonize oxotremorine, and act as analgetics and anticonvulsants. These compounds were found to be nonselective antagonists of histamine, acetylcholine, and BaCl2 in vitro. The compounds exerted effects similar to those of chlorpromazine. Stereoselective differences in activity between diastereoisomers, rather than between enantiomorphs, were generally observed.

Analgesics↗
PubMed1975

7alpha-Carboalkoxy steroidal spirolactones as aldosterone antagonists.

A variety of esters of 17-hydroxy-3-oxo-17alpha-pregn-4-ene-7alpha,21-dicarboxylic acid-gamma-lactone (7a) was synthetized in a sequence using the corresponding 3-oxo-4,6-diene (2) as starting material. The methyl (5), ethyl (7c), and isopropyl (7e) esters as well as the C-1 unsaturated methyl ester (8a) showed good oral and subcutaneous activity (MED less than or equal to 0.41 mg). Some general observations on structure-activity relationships are made.

Administration, Oral↗
PubMed1975

Absolute configuration of the major metabolite of 5,5-diphenylhydantoin, 5-(4'-hydroxyphenyl)-5-phenylhydantoin.

Chemical conversions, optical comparisons, and chiroptical measurements (CD) were employed to determine the absolute configuration of the enantiomers of 5-(4'-hydroxyphenyl)-5-phenylhydantoin (HPPH) (1b and 1c). Studies on a key intermediate, (-)-2-cyclohexyl-2-phenylglycine (5b), led to the reexamination of the well-known rule of Clough-Lutz-Jirgensons. Optical comparisons by means of derivatization into hydantoins and 3-phenyl-2-thiohydantoins (application of Freudenberg's rule of shift) gave conclusions which were consistent with chiroptical measurements on the above compounds. Thus, (-)-HPPH (1c), the major metabolite of 5,5-diphenylhydantoin in man, has the S configuration. This assignment was confirmed by X-ray single-crystal structure analysis of (+)-HPPH 10-(+)-camphorsulfonate (18b).

Circular Dichroism↗