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

TCCA/RSeSeR-Mediated Selenoalkoxy of Allenamides via a Radical Process: Synthesis of Selanyl-allylic N,O-Aminals

An efficient TCCA (trichloroisocyanuric acid)/RSeSeR-mediated selenoalkoxy of allenamides for the construction of selanyl-allylic N,OA-aminal derivatives was developed. The reaction exhibits good functional group tolerance and high efficiency, affording the products in good to excellent yields. Mechanistic investigations indicated that a selanyl-allylic radical intermediate was first formed via the RSe radical added to the central carbon of allenamides, which subsequently furnished highly stable selanyl-allylic carbocation intermediate by abstraction of an electron by the chlorine radical. Moreover, this is the first report of using selenium reagent (RSeCl) to activate allenamides via a radical process.

Synthesis, characterization and hypolipidemic effects of urazine derivatives on rat: Study of molecular modeling and enzyme inhibition

The prevalence of hyperlipidemia has increased dramatically worldwide. It is a major public health threat, characterized by the presence of an abnormal lipid profile, primarily with elevated serum total cholesterol (TC), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL) levels, and reduced high-density lipoprotein (HDL) level. Genetic factors, dietary and lifestyle habits play important roles in hyperlipidemia. It can increase the risk of chronic metabolic disorders, such as obesity, cardiovascular disease, and type II diabetes. The main objective of the present study was to evaluate the effect of urazine derivatives on serum triglyceride, cholesterol, LDL, HDL, and nitric oxide (NO) levels in high-fat diet (HFD)-induced hyperlipidemic rats. Synthetic compounds were prepared and confirmed by spectroscopic methods. Then, 88 male Sprague-Dawley rats were divided into 11 groups: control, HFD-treated group, HFD plus atorvastatin-treated group, and HFD plus 8 synthetic compounds-treated groups. The body weight, triglyceride, cholesterol, LDL, HDL, and NO levels were measured. The data with p < 0.05 were considered significant. The results indicated that HFD significantly increased cholesterol, triglyceride, and LDL levels and decreased NO concentration and HDL level compared to the control group (p < 0.05). However, HFD plus urazine derivatives significantly decreased NO, cholesterol, and triglyceride levels and increased HDL levels compared to the HFD-treated group (p < 0.05). Urazine derivatives may improve liver dysfunction in HFD-induced hyperlipidemic rats by modulation of detoxification enzymes and their anti-oxidant effects and also blood lipid profile.

Regioselective 1,2-addition of allenamides with N-haloimides: synthesis of 2-halo allylic aminal derivatives

A strategy for the synthesis of 2-halo allylic aminal derivatives through regioselective 1,2-addition of allenamides with N-haloimides is presented. This reaction was conducted under very mild conditions and gave up to 99% yield. Moreover, the obtained halides allow functional group diversification by palladium-catalyzed coupling reactions, which could act as potential intermediates for the synthesis of valuable compounds.

Design, Sustainable Synthesis, and Programmed Reactions of Templated N-Heteroaryl-Fused Vinyl Sultams

A de novo design and synthesis of N-heteroaryl-fused vinyl sultams as templates for programming chemical reactions on vinyl sultam periphery or (hetero)aryl ring is described. The key features include rational designing and sustainable synthesis of the template, customized reactions of vinyl sultams at C═C bond or involving N-S bond cleavage, and reactions on the periphery of the heteroaryl ring for late-stage diversification. The simple, easy access to the template coupled with opportunities for the synthesis of diversely functionalized heterocyles from a single template constitutes a rare study in contemporary organic synthesis.

N-Substituted and ring opened saccharin derivatives selectively inhibit transmembrane, tumor-associated carbonic anhydrases IX and XII

A series of N-substituted saccharins incorporating aryl, alkyl and alkynyl moieties, as well as some ring opened derivatives were prepared and investigated as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). The widespread cytosolic isoforms CA I and II were not inhibited by these sulfonamides whereas transmembrane, tumor-associated ones were effectively inhibited, with K_Is in the range of 22.1-481nM for CA IX and of 3.9-245nM for hCA XII. Although the inhibition mechanism of these tertiary/secondary sulfonamides is unknown for the moment, the good efficacy and especially selectivity for the inhibition of the tumor-associated over the cytosolic, widespread isoforms, make these derivatives of considerable interest as enzyme inhibitors with various pharmacologic applications.

Catalytic asymmetric exo-selective [C+NC+CC] reaction

A catalytic asymmetric version of the exo-selective [C+NC+CC] reaction is reported. This multicomponent reaction utilizes a readily prepared achiral glycyl sultam as the "NC" component and commercially available catalyst components. The method can be applied to a variety of aldehydes ("C" component) and activated alkenes ("CC" component) to provide substituted pyrrolidines in good yields and high enantioselectivities. Of particular note is the ability to employ labile enolizable aldehydes (e.g., acetaldehyde and propionaldehyde) in this reaction.

The selective quantification of iron by hexadentate fluorescent probes

The synthesis of four hexadentate fluorescent probes is described, where the fluorescent moiety is based on either coumarin or fluorescein and the chelating moiety is based on either 3-hydroxypyridin-4-one or 3-hydroxypyran-4-one. The fluorescence is quenched when the probe chelating moieties bind iron. The probes were found to be selective for iron over other metals such as Cu, Zn, Ni, Mn and Co. The effect of Cu on fluorescence quenching can be eliminated in the presence of N,N,N',N'-tetrakis(2-pyridylmethyl)-ethylenediamine. Competition studies demonstrate that the exchange of iron between pyridinone-based probes and apotransferrin is very slow. The ability to scavenge iron from oligomeric iron(III) citrate complexes demonstrate that the pyridinone probes scavenges iron faster than deferiprone and desferrioxamine. The fluorescence intensity of the fluorescein-based probe is quantitatively related to the iron concentration with the limit of detection being 10(-8)M.

Synthesis and SAR of α-sulfonylcarboxylic acids as potent matrix metalloproteinase inhibitors

A series of novel carboxylic acid-based alpha-sulfone MMP inhibitors have been synthesized and the in vitro enzyme SAR is discussed. A potential binding mode in the active site of the MMP-9 homology model was highlighted. These compounds are potent MMP-9 inhibitors and are selective over MMP-1.

Microwave assisted synthesis of N-arylphthalamic acids with hyperlipidemic activity

A series of substituted N-arylphthalamic acids 3a-i has been synthesized by the reaction of phthalic anhydride 1 and aryl- or heterocyclic amines 2a-i, in the absence of solvents, in a domestic microwave oven. The formation of nine N-arylphthalamic acids was accomplished in 1-3 min giving excellent yields for compounds 3a-g, but moderate yield of compounds 3h and 3i, respectively. Compounds 3h and 3i are new. Interestingly, N-arylphthalamic acids 3a-i induced hyperlipidemia in Swiss white mice and also increased animals' body weight.

Hypolipidemic activity in rodents of phenobarbital and related derivatives

A series of 5-alkyl-5-phenylbarbituric acid analogues were shown to be potent hypolipidemic agents in rats and mice at 20 mg/kg/day. This dose is lower than that required for hypolipidemic activity for clofibrate and nicotinic acid derivatives in rodents and man. These new derivatives reduced both serum cholesterol and triglyceride levels in rodents by either the oral or intraperitoneal route of administration. Previous studies have demonstrated that similar heterocyclic compounds, i.e. cyclic imides, glutarimides and hydantoins are potent hypolipidemic agents in rodents. The barbituric acid derivatives probably interfered with de novo synthesis of cholesterol and fatty acids in the early steps since the agents inhibit the activities of ATP-dependent citrate lyase and acetyl-CoA synthetase. Triglyceride synthesis may be blocked since the agents inhibited the rate limiting enzyme, sn-glycerol-3-phosphate-acyl-transferase. Rat tissue lipids especially cholesterol and triglycerides were reduced after 14 days treatment. Fecal lipids were increased in cholesterol and phospholipid content by selected compounds. The rat serum lipoprotein after 14 days drug administration showed reduced VLDL-cholesterol and HDL-triglyceride contents. The modulation of the lipid content of the serum lipoproteins by the barbituric acids suggest that these agents may be helpful in treating clinical hyperlipidemic disease states.

Structure activity relationships of imido N-alkyl semicarbazones, thiosemicarbazones and acethydrazones as hypolipidemic agents in rodents

A series of nitrogen substituted N-butan-3-one derivatives of cyclic imides (phthalimide, substituted phthalimide, o-benzosulfimide, 1,8-naphthalimide, 2,3-dihydrophthalazine-1,4-dione and diphenimide) and their semicarbazone, thiosemicarbazone and acethydrazone derivatives were investigated for hypolipidemic activity in rodents. These compounds were generally potent hypolipidemic agents, lowering serum cholesterol levels on an average of 37% and serum triglyceride levels on an average of 29% after 16 days dosing at 20 mg/kg day intraperitoneally (I.P.) in mice. Several analogs, most notably the semicarbazone and acethydrazone derivatives of 1-N-(1,8-naphthalimido)-butan-3-one, demonstrated improved hypocholesterolemic activity relative to their ketone precursors. Similarly, the acethydrazone derivatives generally resulted in improved hypotriglyceridemic activity in each series of 2-(3-oxobutyl)-2,3-dihydrophthalazone-1,4-dione analogs tested. The thiosemicarbazones in mice generally resulted in a loss in hypolipidemic activity. Select compounds, 1-N-3-methylphthalimido butan-3-semicarbazone (Ig) and 1-(4-methoxyphthalazine-1(2H)-one)yl butan-3(N-acetyl)hydrazone (IVg), at 10 mg/kg/day orally administered to rats demonstrated potent hypolipidemic activity after 14 days. These compounds lowered liver, small intestine mucosa and aorta wall tissue lipids, e.g. cholesterol and triglycerides, and raised fecal excretion of cholesterol moderately and of triglyceride significantly. Rat serum lipoprotein fractions after treatment for 14 days showed that the two agents lowered VLDL cholesterol and raised HDL cholesterol content.

Hypolipidemic activity of cyclic imido alkyl ethers, thioethers, sulfoxides, and sulfones

N-Substituted alkyl ethers, thioethers, sulfoxides, and sulfones of cyclic imides (e.g., phthalimide, saccharin, 1,8-naphthalimide, succinimide, and 2,3-dihydrophthalazine-1,4-dione) were shown to have potent hypolipidemic activity at doses of 10 and 20 mg/kg/d in rodents. These N-substitutions afforded no improvement over other known N-substitutions (e.g., butyl, 3-butanone, or the propionic acid derivatives of phthalimide, saccharin, and 2,3-dihydrophthalazine-1,4-dione) compared with the respective parent compounds. However, 2-(methoxyethyl)-1H-benz[de]isoquinoline-1,3-(2H)dione (3a), 2-[2-methylsulfinyl]ethyl-1H-benz[de]isoquinoline-1,3-(2H)dione (3c), 1-(2-methylsulfinyl)-2,5-pyrrolidenedione (4c), and 1-(2-methoxyethyl-2,5-pyrrolidenedione (4a) significantly improved activity compared with parent compounds, as well as previously reported N-substituted analogues, reducing serum cholesterol levels and serum triglyceride levels by 40%. The thioether of succinimide afforded a 54% reduction of serum cholesterol and a 41% reduction of serum triglyceride levels in mice after 16 d. The alkyl thioethers of 1,8-naphthalimide and succinimide significantly lowered cholesterol levels in serum VLDL and LDL, while the alkyl thioethers of succinimide elevated HDL cholesterol content. Tissue lipids were reduced in the liver and aorta by these selected derivatives. The activities of regulatory enzymes in de novo synthesis of hepatic cholesterol and triglyceride were inhibited by the selected 1,8-naphthalimide derivatives. In situ cholesterol and cholic acid reabsorption from intestines were suppressed by the presence of the agents.

The hypolipidemic activity of 1-N-3-methylphthalimido-butan-3-semicarbazone in rodents

1-N-(3-Methylphthalimido)butan-3-one semicarbazone demonstrated potent hypolipidemic activity normal rats and mice and hyperlipidemic diet-induced mice. The compound decreased tissue lip levels and increased the fecal excretion of cholesterol and triglycerides. After 2 weeks of administration, serum lipoprotein levels were modulated so that very low-density lipoprotein (VLDL) and low density lipoprotein (LDL) cholesterol concentrations were reduced and high-density lipoproteins (HDL) cholesterol concentrations were elevated to levels unprecedented by the cyclic imide derivatives previously tested. The VLDL triglyceride content was also reduced. Hepatic in vitro enzymatic studies demonstrated that the compound suppressed the activity of enzymes in the early synthesis of fatty acids and cholesterol and the regulatory enzymes for the de novo synthesis of triglycerides.

Effects of 2-(2,4-dimethylphenyl)indan-1,3-dione on serum lipoprotein and lipid metabolism of rodents

2-(2,4-Dimethylphenyl)indan-1,3-dione was shown to be a potent hypolipidemic agent in rodents, lowering significantly both serum cholesterol and triglyceride levels at 20 mg/kg/day. The agent in vivo inhibited the enzymatic activities of ATP-dependent citrate lyase, acetyl-CoA synthetase, cholesterol-7-alpha-hydroxylase, acyl-CoA cholesterol acyl transferase, sn-glycerol-3-phosphate acyl transferase and phosphatidylate phosphohydrolase. Tissue lipid levels of liver and small intestine also were reduced by the agent. The rat serum lipoprotein lipid content was modulated by the drug, which should be favorable for the removable of cholesterol from peripheral tissue for conduction to the liver for clearance from the body. Low density lipoprotein (LDL) cholesterol levels were reduced after treatment, which suggests that the agent potentially reduces deposition of cholesterol in plaques. If chemotherapy for atherosclerosis is to be successful, then the high density lipoprotein (HDL) cholesterol level needs to be elevated more than 16% to 25%, the level produced by current hypolipidemic agents. 2-(2,4-Dimethylphenyl)indan-1,3-dione offers a 75% increase in HDL cholesterol levels and a 30% reduction of LDL cholesterol levels with a suppression of de novo synthesis of lipids and a reduction of tissue cholesterol deposition.

The hypolipidemic activity of N(4-methyl-phenyl)diphenimide in rodents

N(4-Methyl-phenyl)diphenimide afforded potent hypolipidemic activity in rodents. Serum cholesterol levels were reduced 67% and serum triglyceride were lowered 66% in rats by the drug after two weeks administration orally at 20 mg/kg/day. Rate limiting enzymes in the de novo synthesis of lipids in the liver were suppressed by the drug. Cholesterol was also removed from the body due to the drug accelerating bile excretion. Lipids removed from the blood compartment were not deposited in the organs of the body. VLDL and LDL cholesterol content was significantly reduced in rats treated with the drug with marked increase in HDL cholesterol after two weeks of administration. These data suggest that the drug may be useful in hyperlipidemic states and atherosclerosis in man, thus, further investigation of this class of chemicals is warranted.

Hypolipidemic activity of trimethylamine-carbomethoxyborane and related derivatives in rodents

A number of substituted amine-carboxyborane esters were examined for their hypolipidemic activity in rodents. Trimethylamine-carbomethoxyborane, Me3NBH2C(O)OMe, was observed to be the most effective hypolipidemic agent in the rodent at the low dose of 8 mg/kg/d. This agent effectively increased the high density lipoprotein (HDL) cholesterol content and lowered the low density lipoprotein (LDL) cholesterol and triglyceride contents of rat lipoproteins. Furthermore, the agent accelerated cholesterol excretion from the body of the rat and reduced the activity of the rate-limiting enzyme involved in the de novo synthesis of lipids in the liver. The agent has a safe therapeutic index, and appeared to have more promise as a therapeutic agent than other borane esters.

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.

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.

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.