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J H Musser

Publications and source records attributed to J H Musser.

27 records · Page 2Linked to original sources

REV 2871 (CHBZ): a novel inhibitor of histamine release.

CHBZ is a novel, non-disodium cromoglycate (DSCG)-like, antiallergic drug in vitro. Whereas DSCG loses antisecretory activity with increasing time of preincubation with rat mast cells (RMC) before antigen challenge, and does not inhibit non-immunologically mediated release from human leukocytes, CHBZ exerts long-lived inhibition of both types of release from both types of cells. CHBZ is taken up by RMC in a saturable and time-dependent manner. It is enzymatically converted inside RMC to a DSCG-like metabolite, REV 3579, which, because of its ionic character, accumulates inside the cell. CHBZ, presumably through the action of the REV 3579 generated intracellularly, may mediate long-lived phosphorylation of the same 78 K protein which is transiently phosphorylated upon exposure of RMC to DSCG.

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New developments concerning leukotriene antagonists: a review.

The numbers and subtypes of leukotriene (LT) receptors have only recently been investigated and more work is needed to evaluate the distribution of receptors on tissues and cells in both normal and pathological states. Classification of the heterogeneity of LT receptors may assist in the discovery of new antiallergy and antiinflammatory drugs much in the same way as the study of different adrenergic receptors has benefited cardiovascular drug discovery. The clinical evaluation of the currently available LT antagonists is awaited with interest; however, their therapeutic role in the treatment of asthma, a primary goal for the majority of these agents, will require painstaking clinical appraisal. They seem unlikely to supplant the currently used bronchodilators but may provide a valuable prophylactic adjunct that may suppress some of the inflammatory events that occur in obstructive lung disease. Whether the LT antagonists modify the hyperreactive state that prevails in asthma is also the subject of much speculation.

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Synthesis of [[(naphthalenylmethoxy)- and [[(quinolinylmethoxy)phenyl]amino]oxoalkanoic acid esters. A novel series of leukotriene D4 antagonists and 5-lipoxygenase inhibitors.

A series of novel [[(naphthalenylmethoxy)- and [[(quinolinylmethoxy)phenyl]amino]oxoalkanoic acid esters have been prepared. These compounds were tested as inhibitors of rat polymorphonuclear leukocyte (PMN) 5-lipoxygenase (LO) in vitro and as inhibitors of ovalbumin (OA) and leukotriene D4 (LTD4) induced bronchospasm in the guinea pig (GP) in vivo. Many naphthalenyl compounds were potent inhibitors of 5-LO, and several quinolinyl compounds were potent inhibitors of LTD4-mediated bronchospasms in the GP. The most potent naphthalenyl compound, 4-[[3-(2-naphthalenylmethoxy)phenyl]hydroxyamino]-4-oxobutanoic acid, methyl ester (6v), had an IC50 of 0.6 microM in the 5-LO assay. The most potent compound in vivo, 4-[[3-(2-quinolinylmethoxy)phenyl]hydroxyamino]-4-oxobutanoic acid, methyl ester (6e), had ED50's of 3.3 mg/kg and 27.4 mg/kg (intraduodenally) against LTD4- and OA-induced bronchospasm, respectively. When tested as an antagonist of LTD4-induced contraction of isolated GP tracheal spiral strips, 6e was shown to be a competitive inhibitor with a pKB value of 5.33.

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Synthesis and antiallergic activity of a novel series of 5-lipoxygenase inhibitors.

A series of novel substituted [[(phenoxymethyl)phenyl]amino]oxoalkanoic acid esters have been synthesized. These compounds were tested in vitro for their ability to inhibit the synthesis of 5-hydroxyeicosatetraenoic acid and leukotriene (LT) B4 from rat polymorphonuclear leukocytes (PMN) and in vivo as inhibitors ovalbumin- (OA) and LTD4-induced bronchospasm in the guinea pig. Compounds 5-12 and 25 had IC50's between 1 and 5.6 microM in the rat PMN 5-lipoxygenase assay. Compounds 1, 3, and 16 inhibited OA-induced bronchoconstriction (61%, 64%, and 57%, respectively), but only 1 showed activity against LTD4-induced bronchoconstriction. When tested against LTD4-induced contraction of isolated guinea pig tracheal spiral strips, 1 was a competitive inhibitor with a pKB of 4.94.

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Synthesis and antiallergic activities of 1,3-oxazolo[4,5-h]quinolines.

A series of new 1,3-oxazolo[4,5-h]quinolines has been prepared. These compounds were tested as inhibitors of antigen-induced release of histamine (AIR) in vitro from rat peritoneal mast cells (RMC) and as inhibitors of IgE-mediated passive cutaneous anaphylaxis in the rat (PCA). After several modifications of the original lead, the most potent compound of the series was determined to be 5-chloro-1,3-oxazolo[4,5-h]quinoline-2-carboxylic acid methyl ester (4a). It has an IC50 of 0.3 microM in the RMC assay and an ED50 (intraperitoneal) of 0.1 mg/kg in the PCA test, which is 10 times and 60 times more potent than disodium cromoglycate (DSCG), respectively. Of greater importance, it is orally active (ED50 = 0.5 mg/kg) as an inhibitor of the PCA test.

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1,2,4-Triazolo[4,3-a]quinoxaline-1,4-diones as antiallergic agents.

A series of new 1,4-dihydro-1,2,4-triazolo[4,3-]quinoxaline-1,4-diones has been prepared. These compounds were tested as inhibitors of antigen-induced release of histamine (AIR) in vitro from rat peritoneal mast cells (RMC) and as inhibitors of IgE-mediated rat passive cutaneous anaphylaxis (PCA). Most of this new class of antiallergic agents showed good activity in the RMC and PCA tests. The most potent compound, 2-acetyl-7-chloro-5-n-propyl-1,2,4-triazolo[4,3-a]quinoxaline-1,4-dione (1x), with an I50 value of 0.1 microM, is 30 times more potent than disodium cromoglycate (DSCG) in the RMC assay.

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Synthesis of 2-(2,3-dihydro-2-oxo-1,3,4-oxadiazol-5-yl) benzo heterocycles. A novel series of orally active antiallergic agents.

A series of new 2-(2,3-dihydro-2-oxo-1,3,4-oxadiazol-5-yl) benzo heterocycles has been prepared. These compounds were tested as inhibitors of antigen-induced release of histamine (AIR) in vitro from rat peritoneal mast cells (RMC) and as inhibitors of IgE-mediated rat passive cutaneous anaphylaxis in the rat (PCA). Most of this new class of antiallergic agents showed good activity in the RMC assay. The most potent compound, 3-chloro-2-(2,3-dihydro-2-oxo-1,3,4-oxadiazol-5-yl)benzo[b]thiophe ne (6t), with an I50 value of 0.2 microM, is 15 times more potent than disodium cromoglycate (DSCG) in the RMC assay. Many compounds were orally active in the PCA test, and several of these compounds showed higher potency when given in this way to that shown by DSCG when given intraperitoneally.

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