Pregnancy-associated, lymphocyte-derived suppressor factor inhibits protein kinase C activity.

For successful allogenic pregnancy to occur, suppression of maternal defense responses toward the fetus are vital. Suppressor factors elaborated by decidual cells or immune cells may facilitate this suppression. In order for appropriate cellular responses to occur an intact signal transduction/second messenger system must be present. The calcium/phospholipid-dependent protein kinase, Pk-C, plays an important role in regulating immune responses, and may also be important in regulating uterine cell responses and implantation events. Pk-C activation is necessary for IL-2 synthesis and IL-2 receptor synthesis through activation of the proto-oncogenes c-jun and c-fos. These proto-oncogene gene products combine to form the heterodimer AP-1 which then activates IL-2 gene transcription for both peptide and receptor. If Pk-C activity becomes abrogated then appropriate cell responsiveness is diminished. We have shown that Pk-C activity is decreased in the particulate fraction of 4-7 day pregnant spleen, thymus and draining lymph node (DLN) cells. Spleen cells did not exhibit any change in cytosolic Pk-C activity, the thymus was found to have a decrease in both cytosol and particulate fractions, and the DLN cells exhibited a translocation effect whereby particulate Pk-C decreased and cytosolic Pk-C activity increased. Supernatant from 3-day cultures of DLN cells from pregnant animals was shown to inhibit proliferation of spleen cells. In addition, the supernatant was able to directly lower Pk-C activity. We hypothesize that DLN cells secrete a factor(s) that is able to suppress immune response through abrogation of Pk-C activity, thereby decreasing AP-1 formation resulting in decreased IL-2 synthesis and IL-2 receptor synthesis.

3,7-Diazabicyclane: a new narcotic analgesic.

The synthesis of a series of 9-phenyl-3,7-diazabicyclanes and 9-(m-hydroxyphenyl)-3,7-diazabicyclanes is described. Members of both series were tested for antinociception in rat tail withdrawal and mouse acetic acid writhing assays. Their affinities for opiate receptors in rat brain homogenate were also determined. The 9-phenyl compounds, 1a-c, were inactive. However, the 9-(m-hydroxyphenyl) analogues, 2a-c, were found to possess significant activity in the writhing assay, comparable to that of morphine. All activity was reversed by naloxone.

Alteration of in vivo and in vitro effects of heroin by esterase inhibition.

Selective inhibition of peripheral esterases by tri-ortho-tolyl phosphate in the mouse resulted in an increase in the analgetic activity of heroin, without affecting the activity of morphine. In vitro inhibition of esterases by paraoxon reduced the affinity of heroin for the opiate receptor, while that of morphine was unaffected. These results suggest that both central and peripheral esterases are involved in the metabolism of heroin and that interference with critical esterases can alter its pharmacologic and toxicologic effects.

2.8-A Structure of penicillin-sensitive D-alanyl carboxypeptidase-transpeptidase from Streptomyces R61 and complexes with beta-lactams.

The crystallographic structure of the penicillin-sensitive D-alanyl carboxypeptidase-transpeptidase from Streptomyces R61 has been solved to 2.8-A resolution. The 38,000-dalton serine peptidase has two regions of secondary structure, an alpha/beta cluster, and a region which contains five helical segments. The beta sheet is composed of five beta strands. The tertiary structure has no homology with the classic serine proteases or with the zinc carboxypeptidases. The binding at a common site of three types of beta-lactam (a penicillin, a cephalosporin, a monocyclic beta-lactam) and a desazacyclobutanone has been observed in Fourier difference maps. The binding site sequence is Val-Gly-Ser-Val-Thr-Lys. The beta-lactam ring lies near the enzyme's catalytic serine at position 37, and the C3 substituent of a cephalosporin falls near lysine 40.

Resolution, absolute configuration, and antiarrhythmic properties of the enantiomers of disopyramide, 4-(diisopropylamino)-2-(2-pyridyl)-2-phenylbutyramide.

Disopyramide was resolved by fractional crystallization of its diastereomeric bitartrate salts from methanol-acetone. Diastereomeric sulfonamides prepared from (+)-camphor-10-sulfonyl chloride and the primary amines obtained by LiAlH4 reduction of the resolved bases were separable by high-performance LC and were used to show that within experimental error resolution of disopyramide was complete. The absolute configuration was determined by X-ray crystallography. (+)-[(2R)-(-)-4-(Diisopropylamino)-2-(2-pyridyl)-2-phenylbutyramide (+)-(2R,3R)-bitartrate] crystallizes in space group P212121: a = 14.789 (4), b = 18.151 (4), c = 9.878 (2) A; Z = 4: Dx = 1.225, Dm (flotation C6H6/CCl4) = 1.226 g cm-3. The structure was solved by direct methods. The enantiomeric bitartrates were tested for antiarrhythmic properties. The enantiomeric bitartrate salts were equally effective in prolonging the effective refractory period (ERP) of rabbit ventricle. At 3 x 10(-6) M, the (-)-bitartrate [from (2S)-(+)-disopyramide] increased the ERP 21.8 +/- 6.3 ms and the (+)-bitartrate [from (2R)-(-)-disopyramide] increased the ERP 25.8 +/- 3.6 ms. At 1.5 x 10(-5) M no significant difference was noted, as the increases in the ERP were 41.2 +/- 8.9 and 50.5 +/- 6.3 ms for the (-)- and %+)-bitartrate, respectively.

Synthesis and biological activity of cocaine analogues. 2. 6H-[2]Benzopyrano[4,3-c]pyridin-6-ones.

1,2,3,4-Tetrahydro-2-methyl-6H-[2]benzopyrano[4,3-c]pyridin-6-one (20) and cis- and trans-1,2,3,4,4a,10b-hexahydro-2-methyl-6H-[2]benzopyrano[4,3-c]pyridin-6-one (3a and 3b) were synthesized. The design of 3b was based on the proposal that the active conformation of cocaine is one in which the phenyl and amino groups are arranged in a manner that will superimpose upon a beta-phenethylamine in a trans-staggered conformation. The compounds were compared with cocaine and tropacocaine for their ability to inhibit uptake of [3H]norepinephrine by rat brain synaptosomal preparations. The test compounds (IC50 = 3.2 X 10(-4) M, 20; 6.5 X 10(-4) M, 3a; and 3.2 X 10(-4) M, 3b; respectively) were considerably weaker than cocaine (IC50 = 5.8 X 10(-7) M) and tropacocaine (IC50 = 5.6 X 10(-6) M). Compound 3b showed selectivity at 1 X 10(-5) M for inhibiting the uptake of norepinephrine (36%). It inhibited dopamine (3%) and serotonin (0%) uptake to a much lesser extent, if at all, at this concentration.

Nortropacocaine hydrochloride conformation in aqueous and hydrophobic media.

The nortropacocaine hydrochloride PMR spectra in deuterium oxide and in deuterochloroform differed markedly. A detailed conformational analysis using vicinal 1H-1H coupling constants revealed the molecular conformation to be identical in both solvents. The preferred conformation was one in which the piperidine component existed as a deformed chair. The spectral differences were due to a decreased deshielding of the protonated nitrogen on the neighboring bicyclic ring protons, resulting in chemical shift changes.

Synthesis and biological activity of cocaine analogs I: N-alkylated norcocaine derivatives.

N-Allylnorcocaine, N-dimethylallylnorcocaine, and N-cyclopropylmethylnorcocaine were prepared and examined for cocaine-like activity. The compounds were prepared by alkylation of norcocaine, which was obtained by demethylation of cocaine with 2,2,2-trichloroethyl chloroformate followed by zinc--acetic acid reduction. The compounds were evaluated by comparison with cocaine in causing disruption of milk intake in rats, behavioral modification in squirrel monkeys, and inhibition of 3H-serotonin uptake by rat synaptosomes. The compounds showed cocaine-like activity less potent than cocaine in the latter two tests and were inactive in the milk intake test.

Stereochemistries of geometric isomers of 4-(2-bromo-1,2-diphenylvinyl)phenol, 4-(2-bromo-1,2-diphenyylamine: corrections of the literature.

The stereochemistries of geometric isomers of 4-(2-bromo-1,2-diphenylvinyl)phenol, 4-(2-bromo-1,2-diphenylvinyl)anisole, and 2-[p-(2-bromo-1,2-diphenylvinyl)phenoxy]triethylamine were determined by conversion of the phenolic analog to the ethers and subsequent comparison of physical properties with those of 2-[p-(2-chloro-1,2-diphenylvinyl)phenoxy]triethylamine of known stereochemistry.