Prostaglandins and congeners IX (1). The synthesis of 15-deoxy-16-,17-, or 20-hydroxyprostaglandins and 15-deoxy-15-hydroxymethylprostaglandin E2

Prostaglandin congeners wherein the 15-hydroxy group is moved to the C₁₆, C₁₇, or C₂₀ position or is replaced by a hydroxymethyl group were prepared the 1,4-addition of a lithium trialkyl- -alkenyl alanate to an appropriate cyclopentenone. Several of the 16-hydroxy derivatives showed significant activity as constrictors of the isolated gerbil colon and in bronchodilator and anti-secretory assays.     

Prostaglandins and congeners IX (1). The synthesis of 15-deoxy-16-, 17-, or 20-hydroxyprostaglandins and 15-deoxy-15-hydroxymethylprostaglandin E2

Prostaglandin congeners wherein the 15-hydroxy group is moved to the C₁₆, C₁₇, or C₂₀ position or is replaced by a hydroxymethyl group were prepared via the 1,4-addition of a lithium trialkyl-trans-alkenyl alanate to an appropriate cyclopentenone. Several of the 16-hydroxy derivatives showed significant activity as constrictors of the isolated gerbil colon and in bronchodilator and anti-secretory assays.     

Prostaglandins and congeners. IX. The synthesis of 15-deoxy-16-, 17-, or 20-hydroxyprostaglandins and 15-deoxy-15-hydroxymethylprostaglandin E2.

Prostaglandin congeners wherein the 15-hydroxy group is moved to the C16, C17, or C20 position or is replaced by a hydroxymethyl group were prepared via the 1, 4-addition of a lithium trialkyl-trans-alkenyl alanate to an appropriate cyclopentenone. Several of the 16-hydroxy derivatives showed significant activity as constrictors of the isolated gerbil colon and in bronchodilator and anti-secretory assays.     

Photochromism of halorhodopsin. cis/trans isomerization of the retinal around the 13-14 double bond

The isomeric composition of retinal in membrane-bound and in purified but detergent-free, dark-adapted halorhodopsin was found to be about 70% 13-cis and 30% all-trans. Any illumination increased the all-trans content relative to the dark-adapted state, but blue illumination shifted the isomeric composition more toward all-trans while red illumination of blue-adapted samples shifted it more toward 13-cis. In the presence of chloride this photoisomerization caused the kind of photochromic behavior reported earlier in Smith, S. O., Marvin, M. J., Bogomolni, R. A., and Mathies, R. A. (1984) J. Biol. Chem. 259, 12326-12329, i.e. blue light caused the absorption maximum to move toward longer wavelengths and red light reversed the shift. Only the all-trans chromophore exhibited the complete photocycle described earlier in detergent-solubilized halorhodopsin, and this was the form that could be associated with light-driven chloride transport activity in cell envelope vesicles. In the absence of chloride the spectroscopic changes caused by illumination were much smaller. Reconstitution of bleached preparations with 13-cis- and all-trans-retinal, in the presence and absence of chloride, confirmed that the difference between the absorption maxima of the two isomeric forms of the chromophore is affected by chloride: 13-cis-halorhodopsin absorbs at about 567-568 nm with and without chloride, and the all-trans pigment absorbs near 568 nm in the absence of chloride, but at 578 nm in its presence. The simplest explanation of this finding is that most of the red-shift which accompanies the 13-cis----all-trans transition originates from electrostatic interaction of the retinal with chloride bound in its vicinity.     

Prostaglandins V (1). Synthesis and pharmacology of (+/-)-11-deoxy-10-hydroxyprostaglandin E1 methyl ester

(+/-)-Deoxy-10-hydroxy-PGE1 methyl ester (Va) has been synthesised via conjugate addition of the cuprate (III) to the 5-tetrahydropyranyloxycyclopentenone (IId). Va was found to be 0.1 times as active as PGE1 as a uterine stimulant in the anaesthetized pregnant rat, 0.25 times as active as PGE1 in causing vasodepression in the anaesthetized cat, and approximately equiactive to PGE1 in inducing bronchoconstriction.     

Prostaglandins V (1). Synthesis and pharmacology of (±)-11-deoxy-10-hydroxyprostaglandin E1 methyl ester

(±)-11-Deoxy-10-hydroxy-PGE₁ methyl ester (Va) has been synthesised conjugate addition of the cuprate (III) to the 5-tetrahydropyranyloxycyclopentenone (IId).Va was found to be 0.1 times as active as PGE₁ as a uterine stimulant in the anaesthetized pregnant rat, 0.25 times as active as PGE₁ in causing vasodepression in the anaesthetized cat, and approximately equiactive to PGE₁ in inducing bronchoconstriction.     

Prostaglandins and congeners V. (1) Synthesis of d1-prostaglandin E1, d1-11-deoxyprostaglandin E1, and d1-15-hydroxy-9-oxo-13-cis-prostenoic acid via conjugate addition of 3-trityloxy-1-octenylmagnesium bromides

d1-Prostaglandin E₁ and d1-11-deoxyprostaglandin E₁ are conveniently synthesized via the copper (I) catalyzed conjugate addition of the Grignard reagent prepared from 3-trityloxy-$\text{trans}$-1-octenyl bromide to the appropriate cyclopentenone precursor. The Grignard reagent also afforded the synthesis of a novel structure, d1-15-hydroxy-9-oxo-13-$\text{cis}$-prostenoic acid.     

Synthesis and contractile activity of new acetylenic and allenic analogues of leukotrienes C4 and D4: importance of the Z-11,12 double bond

The (5S,6R) isomers of new acetylenic and allenic analogues of leukotrienes C4 and D4 were synthesized for comparative pharmacological studies on intestinal smooth muscle preparations. These new analogues are poor spasmogenic agonists, the replacement of the 11,12-ene with a relatively more stable triple bond causing an important reduction in intrinsic activity. They did not show any significant antagonist activity. Unexpectedly, these results prove that the 11,12 portion in the triene structure of the lipophilic chain is critical for an agonist activity.     

The detection of the sialoglycoprotease gene and assay for sialoglycoprotease activity among isolates of Pasteurella haemolytica A1 strains, serotypes A13, A14, T15 and A16

Abstract Polymerase chain reaction (PCR) using specific primers to the sialoglycoprotease gene ( gcp ) of Pasteurella haemolytica biotype A, serotype 1 amplified a 1-kb fragment from each of P. haemolytica serotypes A7, A13, A14 and A16, but not T15; which was confirmed by Southern blot hybridization analysis. Using a sialoglycoprotease (Gcp) activity assay, Gcp activity was found in serotypes A13, A14 and A16. Inclusion of these three serotypes confirms that all recognized A biotypes are positive for both gcp gene and activity, with the exception of serotype A11 (which has a different genetic organization and exhibits no Gcp activity). Furthermore, all recognized T biotypes are negative for both the gene and Gcp activity.     

Direct measurement of the lumped constant for 2-deoxy-[1-(14)C]glucose in vivo in human skeletal muscle

The lumped constant (LC) is used to convert the clearance rate of 2-deoxy-D-glucose (2-DG(CR)) to that of glucose (Glc(CR)). There are currently no data to validate the widely used assumption of an LC of 1.0 for human skeletal muscle. We determined the LC for 2-deoxy-[1-(14)C]glucose (2-DG) in 18 normal male subjects (age, 29+/- 2 yr; body mass index, 24.8+/-0.8 kg/m(2)) after an overnight fast and during physiological (1 mU x kg(-1) x min(-1) insulin infusion for 180 min) and supraphysiological (5 mU x kg(-1) x min(-1) insulin infusion for 180 min) hyperinsulinemic conditions. Normoglycemia was maintained with the euglycemic clamp technique. The LC was measured directly with the use of a novel triple tracer-based method. [3-(3)H]glucose, 2-[1-(14)C]DG, and [(12)C]mannitol (Man) were injected as a bolus into the brachial artery. The concentrations of [3-(3)H]glucose and 2-[1-(14)C]DG (dpm/ml plasma) and of Man (micromol/l) were determined in 50 blood samples withdrawn from the ipsilateral deep forearm vein over 15 min after the bolus injection. The LC was calculated by a formula involving blood flow calculated from Man and the Glc(CR) and 2-DG(CR). The LC averaged 1.26+/-0.08 (range 1.06-1.43), 1.15+/-0.05 (0.99-1.39), and 1.18+/-0.05 (0.97-1.37) under fasting conditions and during the 1 and 5 mU x kg(-1). min(-1) insulin infusions (not significant between the different insulin concentrations, mean LC = 1.2, P<0.01 vs. 1.0). We conclude that, in normal subjects, the LC for 2-DG in human skeletal muscle is constant over a wide range of insulin concentrations and averages 1. 2.     

Synthesis and opioid activity of 2-substituted dynorphin A-(1-13) amide analogues.

A series of 2-substituted dynorphin A-(1-13) amide (Dyn A-(1-13)NH2) analogues was prepared by solid phase peptide synthesis and evaluated for opioid receptor affinities in radioligand binding assays and for opioid activity in the guinea pig ileum (GPI) assay. Amino acid substitution at the 2 position produced marked differences in both opioid receptor affinities and potency in the GPI assay; Ki values for the analogues in the radioligand binding assays and IC50 values in the GPI assay varied over three to four orders of magnitude. The parent peptide, Dyn A-(1-13)NH2, exhibited the greatest affinity and selectivity for kappa receptors and was the most potent peptide examined in the GPI assay. The most important determinant of opioid receptor selectivity and opioid potency for the synthetic analogues was the stereochemistry of the amino acid at the 2 position. Except for [D-Lys2]Dyn A-(1-13)NH2 in the kappa receptor binding assay, the analogues containing a D-amino acid at position 2 were much more potent in all of the assays than their corresponding isomers containing an L-amino acid at this position. The L-amino acid-substituted analogues generally retained some selectivity for kappa opioid receptors. The more potent derivatives with a D-amino acid in position 2, however, preferentially interacted with mu opioid receptors. Introduction of a positively charged amino acid into the 2 position generally decreased opioid receptor affinities and potency in the GPI assay.