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J M Chapman

Publications and source records attributed to J M Chapman.

At least 55 records · Page 3Linked to original sources

Comparison of the hypolipidemic activity of cyclic vs. acyclic imides.

Two series of nitrogen-substituted cyclic and acyclic imides were examined for hypolipidemic activity in mice after dosing for 16 days at a dose of 20 mg/kg per day. The hypolipidemic activity of the unsubstituted, N-butyl, N-3-oxobutyl, and N-2-carboxyethyl derivatives of diacetimide and succinimide were compared as well as the unsubstituted and N-substituted dibenzimide and diphenimide. It was shown that an imide functionality incorporated into a ring was not necessary for hypocholesterolemic activity. Good hypocholesterolemic activity was observed in both series of acyclic and cyclic imides. However, a cyclic imido structure was a necessary requirement for good hypotriglyceridemic activity. A decrease in hypotriglyceridemic activity was noted when comparing the cyclic imides to their respective acyclic congeners.

Animals↗

Synthesis and evaluation of the antitumor properties of esters of 2-furoic acid and 2-furylacrylic acid.

A series of activated and nonactivated esters of 2-furoic and 2-furylacrylic acids were synthesized and examined for antineoplastic activity in the Ehrlich ascites carcinoma screen at 20 mg/kg/d. 2-Furoic acid and 2-furylacrylic acid demonstrated potent activity, as did the methyl and cyanomethyl esters of each series. The vinyl ester of 2-furoic acid possessed antineoplastic activity. However, the ethyl and D,L-tetrahydropyranyl esters of each series were inactive in the tumor screen.

Animals↗

Hypolipidemic activity of 3-N-(1',8'-Naphthalimido)propionic acid in rodents.

3-N-(1',8'-Naphthalimido)propionic acid was synthesized and shown to effectively lower both serum cholesterol and triglyceride levels in rats and mice. In hyperlipidemic mice, serum lipid levels were lowered significantly, approaching normal levels of cholesterol and below normal levels of triglyceride. The serum lipid levels were reduced due to accelerated clearance of cholesterol via the biliary route as well as a lowering of available acetyl CoA in the cytoplasm for liver de novo cholesterol and triglyceride syntheses. The liver regulatory enzyme of fatty acid and triglyceride syntheses were depressed by drug treatment. Significant reduction of liver lipids as well as the lipid content of the lipoprotein fractions were observed. The agent possessed a safe therapeutic index when used as a hypolipidemic agent.

Animals↗

Hypolipidemic activity of phthalimide derivatives V: Reduced and hydrolytic products of simple cyclic imides.

A series of cyclic imides and related compounds have previously been shown to possess hypolipidemic activity at the low dose level of 20 mg/kg/d. Hydrolytic and reduced products of the cyclic imides were synthesized and examined to discern if possible metabolic products were the active chemical species of these hypolipidemic agents. Phthalimide proved to be the most active cyclic imide tested. Unfortunately, the new products did not, in general, improve hypolipidemic activity in rodents. The exceptions were piperidine which demonstrated improved hypotriglyceridemic activity, and 3,4,5,6-dibenzohomopiperidin-2-one, which demonstrated improved hypocholesterolemic activity compared to phthalimide.

Animals↗

Mortality due to all causes and to cardiovascular diseases among seven race-ethnic populations in Los Angeles County, 1980.

Mortality rates during 1980 in Los Angeles County are presented for Whites, Blacks, Hispanics, and Americans of Japanese, Chinese, Philippine, and Korean descent, seven groups with varying patterns of migration during the prior decade. For all causes of death, age- and sex-adjusted rates were highest among Blacks, intermediate among Whites and Hispanics, and substantially lower among Asians and Pacific Islanders. A similar observation was made for the major cardiovascular diseases and for diseases of the heart. In contrast, the mortality rates for cerebrovascular diseases exhibited a slightly different pattern, with Blacks again highest, Whites and Japanese being intermediate, and Hispanics, Filipinos, Chinese, and Koreans being lowest. The descriptive information suggests several areas for further research into the effect of various cultural or lifestyle patterns on the occurrence of cardiovascular disease.

Adult↗

Hypolipidemic activity of substituted 2-pyrrolidinones in rodents.

A series of substituted 2-pyrrolidinones was evaluated for hypolipidemic activity at 20 and 30 mg/kg/day in CF1 male mice. 4-Phenyl-5,5-dicarbethoxy-2-pyrrolidinone was the most potent compound at 30 mg/kg/day, reducing serum triglyceride levels 52% after 14 days of dosing and serum cholesterol levels 48% after 16 days of dosing. 4-Phenyl-5-carbethoxy-2-pyrrolidinone and 4-phenyl-3,5,5-tricarbethoxy-2-pyrrolidinone also demonstrated significant activity. Those compounds which contained a phenyl substituent were more potent than either the unsubstituted, the alkyl, or the dicarbethoxy 2-pyrrolidinone analogues.

Animals↗

Antihyperlipidemic activity of phthalimide analogues in rodents.

Phthalimide analogues have been shown to effectively lower serum cholesterol and triglyceride levels in rats and mice. The mode of action of these agents was not to suppress the appetite of animals, but rather to reduce the activities of key enzymes in the early synthesis of liver cholesterol and fatty acids in the triglyceride pathway. Phthalimide analogues were effective in accelerating biliary excretion of cholesterol and blocking its absorption from the gut. After 16 days dosing, it was evident that higher levels of lipids were being excreted than in control mice. The major serum lipoprotein fractions were reduced in cholesterol, triglyceride, and neutral lipid content, but not phospholipid content in rats after 14 days of administration.

Animals↗

Antihyperlipidemic activity of saccharin analogues in rodents.

Saccharin analogues were observed to be potent antihyperlipidemic agents at 20 mg/kg/day in rodents, significantly reducing both serum cholesterol and triglyceride levels in both normal and atherogenic mice. The saccharin analogues suppressed in vitro and in vivo liver enzymatic activity of acetyl-CoA synthetase, citrate lyase, and mitochondrial citrate exchange leading to a reduction of available cytoplasmic acetyl-CoA, which is required for the synthesis of cholesterol and fatty acids. Liver acetyl-CoA carboxylase, phosphatidate phosphohydralase, and glycerol-3-phosphate acyl transferase activities were markedly reduced by the saccharin analogues. Suppression of these enzymes would lead to a reduction of triglyceride synthesis. The saccharin analogues accelerated bile excretion of cholesterol metabolites and increased the fecal excretion of the cholesterol, triglycerides, neutral lipids, and phospholipids. The liver and plasma lipoprotein lipid content (including cholesterol, triglycerides, and neutral lipids) was markedly reduced by the saccharin analogues, whereas phospholipid content was elevated. The reduction of lipid content of serum chylomicron, very low-density, low-density, and high-density lipoprotein fractions by the saccharin analogues indicates that these agents may be useful in controlling hyperlipidemic diseases where specific lipoprotein fractions are elevated.

Animals↗

Hypolipidemic activity of phthalimide derivatives IV: Further chemical modification and investigation of the hypolipidemic activity of N-substituted imides.

A further investigation of N-substituted derivatives of phthalimide for hypolipidemic activity has revealed that the chain length, as well as the type of substitution on the N-alkyl chain of phthalimide is critical for biological activity. In these studies the hypolipidemic activity was not improved by extending the chain length beyond five carbon atoms in the alkyl and alkanoic acid series. Imido nitrogen substituents, other than alkanoic acids, methyl ketones, and alkyl groups, caused a reduction in hypolipidemic activity, e.g., hydroxy, amino, hydroxymethyl, or carbethoxy. Reduction of the keto group in the side chain to an alcohol, as well as forming derivatives of the keto group, did not improve the hypolipidemic activity with the exception of 1-N-phthalimidobutan-3-one semicarbazone. This compound demonstrated improved hypocholesterolemic activity over phthalimide and 1-N-phthalimidobutan-3-one. Substitution of the 3-position of the aromatic moiety of phthalimide with an amino or nitro group, as well as substituting a pyridine or cyclohexyl ring for the phenyl ring, led to the loss of hypolipidemic activity.

Animals↗

Hypolipidemic activity of phthalimide derivatives. 2. N-phenylphthalimide and derivatives.

A series of substituted N-phenylphthalimide derivatives was synthesized and examined for their ability to lower serum cholesterol and triglyceride levels in mice at 20 (mg/kg)/day, ip. Of the newly synthesized compounds, the most potent compound, o-(N-phthalimido)acetophenone, lowered serum cholesterol 57% after 16 days and lowered serum triglyceride levels 44% after 14 days. o-(N-Phthalimido)acetophenone was observed to be active in both normogenic (normal blood lipids levels) and hyperlipidemic mice and normogenic rats. In the latter, the reduction of serum lipids was reversible. The mode of this compound appeared to be multiple, including blockage of the de novo synthesis of lipids and acceleration of the excretion of lipids. The lipoprotein fractions of rat blood were reduced significantly in cholesterol, triglyceride, and neutral lipid content after 14 days treatment with o-(N-phthalimido)acetophenone.

Acetate-CoA Ligase↗

Hypolipidemic activity of phthalimide derivatives. 3. A comparison of phthalimide and 1,2-benzisothiazolin-3-one 1,1-dioxide derivatives to phthalimidine and 1,2-benzisothiazoline 1,1-dioxide congeners.

Previously it has been observed that N-substituted phthalimide derivatives with chain lengths of four carbon or oxygen atoms showed potent hypolipidemic activity in rodents at 20 (mg/kg)/day ip. The 1,2-benzisothiazolin-3-one 1,1-dioxide (saccharin) nucleus, itself, had also been observed to be active at the same dose. An investigation was undertaken to examine a series of 1,2-benzisothiazolin-3-one 1,1-dioxide analogues for their hypolipidemic activity in mice and to compare them to their respective phthalimide congeners. In addition, a series of 1,2-benzisothiazoline 1,1-dioxide and phthalimidine analogues was prepared, and their hypolipidemic activity was compared to the phthalimide analogues. These studies show that the respective congeners of 1,2-benzisothiazolin-3-one 1,1-dioxide compared favorably to phthalimide congeners in reducing serum triglyceride and cholesterol levels in male CF1 mice at 20 (mg/kg)/day ip. Of the saccharin derivatives, 3-oxo-1,2-benzisothiazoline-2-propionic acid 1,1-dioxide was the most effective in lowering serum cholesterol levels by 53% after 16 days dosing and 3-oxo-1,2-benzisothiazoline-2-valeric acid 1,1-dioxide lowered serum triglycerides 56% after 14 days dosing. The 1,2-benzisothiazoline 1,1-dioxide and phthalimidine compounds were less active as hypolipidemic agents than their 1,2-benzisothiazolin-3-one 1,1-dioxide and phthalimide analogues, respectively.

Animals↗

Effects of imide analogs on enzymes required for cholesterol and fatty acid synthesis.

Twelve imide analogs were examined for their ability to lower serum cholesterol and triglyceride levels in mice. Potent activity was observed for compounds containing a phthalimide or saccharin ring structure. The ability to lower serum cholesterol appears to be related to the ability to suppress acetyl-CoA synthetase activity. The availability of acetyl-CoA in the cytoplasm is a key regulatory component for cholesterol and fatty acid synthesis. The capacity to reduce serum triglycerides was related directly to the ability of the compound to inhibit acetyl-CoA carboxylase activity, the regulatory enzyme of fatty acid synthesis.

Acetate-CoA Ligase↗

Studies on premedication and ventilatory responses to minaxolone.

The effect of three premedications on induction, maintenance and recovery characteristics of minaxolone as a supplement to nitrous oxide and oxygen anesthesia were studied in 70 patients. Morphine and atropine premedication provided superior operative conditions with fewer side-effects when compared with atropine alone or diazepam and atropine. Recovery was significantly longer after minaxolone compared with a similar group of patients given Althesin. The ventilatory responses to the induction of anesthesia with minaxolone were measured in 25 patients. All patients showed an increase in respiratory frequency and a decrease in tidal volume. This effect was most marked in the group premedicated with diazepam and atropine.

Adult↗

Hypolipidemic activity of phthalimide derivatives. 1. N-Substituted phthalimide derivatives.

The general lipid-lowering action of the N-substituted phthalimide derivatives reported herein, as well as the activity of potassium phthalimide, implicates the phthalimide moiety as possessing hypolipidemic activity in rodents. Compounds containing substituents with chain lengths of four carbon or oxygen atoms showed the best hypolipidemic activity in the series tested. Tests involving 1-N-phthalimidobutan-3-one demonstrated a dose-dependent hypolipidemic action free of estrogenic side effects, with no apparent deposition of cholesterol in body organs, and with a high therapeutic index. Further work on the hypolipidemic activity of phthalimido, as well as other imido compounds, is underway.

Animals↗

Coronary risk and estrogen use in postmenopausal women.

Of some 15,500 women resident in a retirement community during an 11 year interval, 220 suffered a cardiologically ascertained first myocardial infarction. A case-control study demonstrated no association between estrogen use and myocardial infarction. The observed lack of association may be explained by an already high coronary risk in this age group, by the low daily estrogen dose, and by the short duration of estrogen use. The well-known association between hypertension and myocardial infarction was confirmed.

Adult↗