Inhibition of aromatic amino acid decarboxylase by a group of non-steroidal anti-inflammatory drugs

In vitro inhibition of aromatic amino acid decarboxylase (AAD) by eight nonsteroidal anti-inflammatory drugs (NSAIDs) was studied. The most potent inhibitors were fenamates (IC50 for tolfenamate was 4.4 x 10(-5) M), while fluorinated biphenylic compounds (flobufen and 2',4'-difluorobiphenyl-4-yl acetate) and propionic acid derivatives (ibuprofen, ketoprofen, fenoprofen) were one order weaker. The in vitro inhibition of AAD by the compounds studied is probably not strong enough to contribute to their in vivo anti-inflammatory effects.

Metabolic chiral inversion of 2-arylpropionates in rat H4IIE and human Hep G2 hepatoma cells. Relationship to in vivo metabolism

The inversion of 2-arylpropionic acids (2-APAs) has been investigated in vitro using rat H4IIE and human Hep G2 hepatoma cells in continuous culture. The effect of substrate concentration (15-150 micrograms/mL), cell density (1.5-12 x 10(6) cells/dish) and serum content of the culture medium (0-20%) on inversion was examined in rat H4IIE hepatoma cells using R-ibuprofen as model compound. Increasing R-ibuprofen concentrations and decreasing serum content of the medium resulted in increased inversion whereas variation of cell density had no effect. Furthermore, rat H4IIE and human Hep G2 hepatoma cells were incubated with the individual enantiomers of ibuprofen, ketoprofen and flurbiprofen under optimized culture conditions (serum-free culture medium). The elimination rate constants (kel) and fractions inverted (Fi) were determined. Although inversion occurred slowly in the tumor cells and thus long incubation periods (120 hr) were required, the hepatoma cells were nevertheless able to mimic qualitatively the species and substance specificity of inversion of 2-APAs as observed in vivo.

A novel synthesis and potent antiinflammatory activity of 4-hydroxy-2(1H)-oxo-1-phenyl-1,8-naphthyridine-3-carboxamides

New antiinflammatory agents 4-hydroxy-2(1H)-oxo-1-phenyl-1,8-naphthyridine-3- carboxamides 7 were designed and synthesized via a valuable intermediate, 1-phenyl-2H-pyrido[2,3-d][1,3]oxazine-2,4(1H)-dione (9). The nature of substituents on the amide nitrogen had a pronounced effect on antiinflamatory activity. Studies of structure-activity relationships led to compounds 33 and 34 bearing a pyridine ring on the amide nitrogen. Compounds 33 and 34 were active against carrageenin-, zymosan-, and arachidonic acid-induced rat paw edemas and also potently inhibited the reversed passive Arthus reaction in rats. Thus, they possess a broader spectrum of antiinflammatory activity than the classical nonsteroidal antiinflammatory drugs (NSAIDs) such as indomethacin and piroxicam.

Influence of limonene and laurocapram on percutaneous absorption of nonsteroidal anti-inflammatory drugs

The promoting effect of cyclic monoterpenes, 1% limonene (CAS 5989-27-5) and 1% cineole (CAS 470-82-6), on percutaneous absorption of nonsteroidal anti-inflammatory drugs was investigated in the rats. Compared with 1% laurocapram, drug absorption from the gel ointments was significantly more enhanced by addition of 1% limonene, while without any enhancer only ibuprofen penetrated across the skin in the limited amount. When using formulation with propylene glycol or 50% propylene glycolethanol solution, instead of carboxyvinyl polymer gel, percutaneous absorption significantly decreased and neither limonene nor cineole or laurocapram were capale to promote percutaneous absorption of flufenamic acid to sufficient serum level. Cineole and limonene were also evaluated in permeation experiments in vitro. Enhancement ability of limonene in the gel oinment was approximately 5 times higher comparing with enhancement ratio of cineole, while in 100% propylene glycol enhancement ability of both cyclic monoterpenes was equal. Good correlation was observed between in vivo and in vitro experiments. Evaluation of solubility proved that in the gel ointment simulated as water-ethanol solution were relatively best condition for percutaneous absorption of flufenamic acid when comparing with propylene glycol or 50% propylene glycol-ethanol solution.

Photochemistry of tiaprofenic acid, a nonsteroidal anti-inflammatory drug with phototoxic side effects

The phototoxic nonsteroidal anti-inflammatory drug tiaprofenic acid (1) is photolabile under aerobic conditions. Irradiation of a methanol solution of 1 under oxygen produces the photoproducts 2, 3, 4, and 5, and also produces a singlet oxygen as evidenced by trapping with 2,5-dimethylfuran.

Bis basic substituted diaminobenzobisthiazoles as potential antiarthritic agents

A series of benzobisthiazoles were screened for antiinflammatory activity in the carrageenan paw edema and adjuvant arthritis tests. Compound 26, 2,6-bis(N,N-diethylamino)benzo[1,2-d:5,4-d']bisthiazole, was found to inhibit the swelling of the uninjected paw in the prophylactic adjuvant arthritis model with an ED50 of 2.3 mg/kg orally. As with most compounds of this series, 26 was inactive in acute model of inflammation, such as paw edema; like steroids, it showed activity in the granuloma pouch assay but did not inhibit cyclooxygenase, indicating a mode of action different from the classical nonsteroidal antiinflammatory drugs (NSAID's). At doses higher than those producing antiinflammatory activity, 26 had some immunoregulating properties.

Structural study of benzidamine salicylate in the solid state and in solution

The vibrational (IR and Raman) and 1H and 13C NMR spectra of the analgesic and anti-inflammatory benzidamine salicylate (Benzasal) have been examined, and the results are described. The crystal structure of this compound has been determined by X-ray diffraction. To assist in interpretation of the spectroscopic data, some measurements of benzidamine, benzidamine hydrochloride, and salicylic acid have also been made. The most important intermolecular interactions of benzidamine salicylate in the solid state are N(+)H...O(-)...-C hydrogen bonds involving both salicylate oxygen atoms (d = 2.658 A and 3.228 A). At least the stronger hydrogen bond remains in CDCl3 solution. Moreover, the strong intramolecular hydrogen bond O-H...O(-)...-C within the salicylate anion has also been observed in the solid state and in solution.

Tensides from the group of propylene oxide and ethylene oxide copolymers. X. Solubilization of acetylsalicylic acid by polyetherodiol micelles

The process of structural solubilization of acetylsalicylic acid in balanced systems (weight-balanced) by micelles of Rokopols of 30p160 and 30p60 types and, for comparison, by those of F-68 and F-108 Pluronics was investigated. The determined viscosity and hydrodynamic parameters allowed for the calculation of solubilizing activity of polyetherodiol micelles--n(s(A)). The results of the investigation point at Rokopols as an excipient, which may help to obtain new drug delivery systems.

Chirality in antirheumatic drugs

Use of chiral molecules in clinical practice may cause problems because different chiral forms of a drug (enantiomers) may have different biological activities--yet clinicians have little awareness of these risks. After discussion of the chemical conventions used to describe chirality, examples of the influence of chirality on the efficacy and toxicity of antirheumatic drugs are given. It is recommended that single enantiomers should be used in biological experiments and clinical trials.

Development of affinity labeling agents based on nonsteroidal anti-inflammatory drugs: labeling of the nonsteroidal anti-inflammatory drug binding site of 3 alpha-hydroxysteroid dehydrogenase

Nonsteroidal anti-inflammatory drugs (NSAIDs) exert their effect by inhibiting the target enzyme cyclooxygenase (prostaglandin H2 synthase); however, little is known about the peptides comprising its NSAID binding site. Hydroxyprostaglandin dehydrogenases also bind NSAIDs, but their NSAID binding sites have not been well characterized. Using existing synthetic strategies, we have incorporated the bromoacetoxy affinity labeling moiety around the perimeter of two potent NSAIDs, indomethacin and mefenamate, a N-phenylanthranilate. The compounds synthesized were 1-(4-(bromoacetamido)benzyl)-5-methoxy-2-methylindole-3-acetic acid (1), 3-(2-(2-bromoacetoxy)ethyl)-1-(4-chlorobenzyl)-5-methoxy-2-methylindole (2), 4-(bromoacetamido)-N-(2,3-dimethylphenyl)anthranilic acid (3), N-(3-(bromoacetamido)phenyl)-anthranilic acid (4), and N-(4-(bromoacetamido)phenyl)anthranilic acid (5). To access whether these compounds have general utility in labeling NSAID binding sites, the compounds were evaluated as affinity labeling agents for 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) from rat liver cytosol. This enzyme displays 9-, 11-, and 15-hydroxyprostaglandin dehydrogenase activity, is inhibited potently by NSAIDs, and is homologous to bovine lung prostaglandin F synthase. Compounds 1-5 were shown to affinity label the NSAID binding site of 3 alpha-HSD. They inactivated 3 alpha-HSD through an E.I complex in a time- and concentration-dependent manner with t1/2 values ranging from seconds to hours. Ligands that compete for the active site of 3 alpha-HSD (NAD+ and indomethacin) afforded protection against inactivation, and the inactivators could demonstrate competitive kinetics against 3 alpha-hydroxysteroid substrates by forming an E.NAD+.I complex.(ABSTRACT TRUNCATED AT 250 WORDS)

Chiral inversion of 2-arylpropionic acid non-steroidal anti-inflammatory drugs--II. Racemization and hydrolysis of (R)- and (S)-ibuprofen-CoA thioesters

The inversion of 2-arylpropionic acids (2-APAs) has become the subject of much attention. It is a unique reaction specific to this group of drugs. Inversion proceeds via stereoselective activation of the R-enantiomer to its CoA thioester whereby it is then racemized and hydrolysed to release free drug. The racemization and hydrolysis processes have been examined in this study using chemically synthesized CoA thioesters of the ibuprofen enantiomers and in vitro models employing rat liver homogenate and the mitochondrial and microsomal fractions as the source of the 'racemase' enzymes. Rat liver homogenate mediated the racemization and hydrolysis of both (R)- and (S)-ibuprofen-CoA thioesters. The rat liver mitochondrial fraction similarly mediated racemization and hydrolysis of both CoA thioesters. There was less racemase activity in the rat liver microsomal fraction and the data indicated that this fraction may contain two hydrolases which act separately on the (R)- and (S)-ibuprofen-CoA thioesters. The data are further evidence that the stereoselectivity of the CoA synthetase controls the overall stereoselectivity of inversion.

Low molecular weight proteins as carriers for renal drug targeting: naproxen-lysozyme

Low molecular weight proteins (LMWPs), such as lysozyme, may be suitable carriers to target drugs to the kidney. In this study the antiinflammatory drug naproxen was covalently bound to lysozyme (1:1). Pharmacokinetics of the conjugate, naproxen-lysozyme (nap-LYSO), were compared to that of an equimolar mixture of uncoupled naproxen with lysozyme in freely moving rats. Similar plasma kinetics and organ distribution for native lysozyme and the drug conjugate were observed (Clp = 1.2 and 1.1 ml/min; t1/2,beta = 85 and 75 min, respectively). In case of the uncoupled naproxen-lysozyme mixture, a monoexponential plasma disappearance of naproxen with a t1/2 of 2.8 hr was observed, coinciding with urinary excretion of naproxen metabolites (mainly 6-desmethylnaproxen sulfate; 6-DMN-S) between 2 and 8 hr after injection. Urinary recovery of total metabolites was 59% of the naproxen dose. In contrast, after injection of covalently bound naproxen, plasma levels of the parent drug were below the detection level, whereas naproxen was recovered as 6-DMN-S in urine over a period from 4 to 30 hr. However, only 8% of the administered dose was recovered as 6-DMN-S in urine, whereas 50% of the dose was recovered as naproxen metabolites in feces. Incubation experiments using purified renal tubular lysosomal lysates revealed that naproxen-lysozyme degradation ultimately results in a stable naproxen amino acid catabolite, naproxen-lysine (nap-lys). Hepatic uptake and biliary excretion of this catabolyte were demonstrated in isolated perfused rat livers. Further, an equipotent pharmacological activity relative to parent naproxen was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Non polar constituents of Stenomesson variegatum (R. et P.) Macbr

Hydrocarbons, triterpenoids and sterols were determined in Stenomesson variegatum (R. et P.) Macbr. (Amaryllidaceae), a plant used in traditional peruvian medicine as an antiinflammatory. An unusual presence of odd hydrocarbons was found, whereas triterpenoidic and sterolic fractions are quite usual and simple.

Allergic photocontact dermatitis due to suprofen. Photopatch testing and cross-reaction study

We report 5 cases of photocontact dermatitis due to suprofen, a nonsteroidal anti-inflammatory drug introduced to the Japanese market in 1989, and available as a 1% ointment. The patients developed pruritic eczematous lesions after applying the ointment for from 2 weeks to 3 months. All 5 patients reacted positively to photopatch testing with ultraviolet A (UVA) and suprofen down to 0.1-0.01% pet., and 3 patients showed positive reactions with ultraviolet B (UVB) and suprofen down to 1.0-0.1%. Moreover, all patients showed a cross-reaction with tiaprofenic acid, which has a very similar chemical structure to suprofen. However, there was no cross-reaction between suprofen and ketoprofen. Prescribers should be aware of the existence of photocontact sensitivity due to these drugs.

Anti-inflammatory effect of Zingiber cassumunar Roxb. and its active principles

The present study was carried out to elucidate the anti-inflammatory effect of the methanol extract obtained from the rhizomes of Zingiber cassumunar Roxb. and its active principles. The methanol extract was partitioned between ether and water, and then the ether-soluble fraction was extracted with n-hexane. The n-hexane-soluble fraction was chromatographed and part of the fraction was rechromatographed by silica gel column. Three compounds were isolated from the n-hexane-soluble fraction and the chemical structures of these compounds were identified as (E)-1-(3,4-dimethoxyphenyl)but-1-ene, (E)-1-(3,4-dimethoxyphenyl)butadiene and zerumbone. The anti-inflammatory activity of these fractions was investigated on carrageenin-induced edema in rats, as well as on acetic acid-induced vascular permeability and writhing symptoms in mice. The methanol extract (p.o.) showed both anti-inflammatory activity and analgesic activity. These activities shifted successively to ether-soluble and n-hexane-soluble fractions and to (E)-1-(3,4-dimethoxyphenyl)but-1-ene. These results suggest that the anti-inflammatory action and analgesic action of Zingiber cassumunar is the result of the (E)-1-(3,4-dimethoxyphenyl)but-1-ene that it contains.

Vidalols A and B, new anti-inflammatory bromophenols from the Caribbean marine red alga Vidalia obtusaloba

Chemical studies of the Caribbean red alga Vidalia obtusaloba have resulted in the isolation of two new bromophenolic metabolites, vidalols A and B (1, 2). The new compounds were discovered as part of an organized effort to isolate new naturally-occurring anti-inflammatory agents with a focus upon those which may function through the inhibition of phospholipase A2.

Pharmacokinetic, biochemical and tolerance studies on carprofen in the horse

Carprofen, a non-steroidal anti-inflammatory drug (NSAID) was administered to three Thoroughbred geldings and three Shetland ponies to determine its plasma disposition and tolerance. The main pharmacokinetic characteristics of carprofen in horses and ponies were a volume of distribution of 0.08 to 0.32 litres/kg (mean +/- se = 0.23 +/- 0.04) a systemic clearance of 26.4 to 78.5 ml/min (mean +/- se = 44.9 +/- 8.0) and a plasma elimination half-life of 14.5 to 31.4 h (mean +/- se = 21.9 +/- 2.3). There was no evidence of any accumulation of carprofen in plasma when the drug was given orally at a dose rate of 0.7 mg/kg for 14 consecutive days. Carprofen was well tolerated following intravenous (iv) and oral administration. Intramuscular (im) administration resulted in elevated levels of plasma creatine kinase suggesting muscle cell damage. According to the results of this study carprofen can be regarded as a long-acting NSAID in horses from a pharmacokinetic point of view. Either iv, im or the oral route of administration could be used to achieve high carprofen plasma concentrations.

Peroxide chemistry of triaryl-substituted imidazoles. Fenflumizole, a non-steroidal, anti-inflammatory agent

Fenflumizole, [2-(2,4-difluorophenyl)4,5-bis(4-methoxyphenyl)imidazole] is a nonsteroidal, anti-inflammatory analgesic. It reacts quantitatively with 1O2 forming 2-(2,4-difluorophenyl)-4-hydroperoxy-4,5-bis(4-methoxyphenyl)imidazole in a reversible reaction. In ethanol solution at ambient temperatures, the peroxide regenerates parent fenflumizole and 1O2 together with minor quantities of other products. The structures of those products point to the intermediacy of a 1,3-endoperoxide and a dioxetane. These observations may be relevant to the biological activity of fenflumizole.

Abnormal desolvation behavior on solvate of etodolac sodium salt

Sodium salts of (+/-)- and (+)-etodolac were prepared and characterized: the (+/-)-sodium salt contained 5.26% water and 1.09% acetonitrile, and the (+)-sodium salt contained 1.14% water and 2.02% other volatiles (methanol and acetonitrile). Abnormal hygroscopic behavior of the (+/-)-etodolac sodium salt was observed; that is, it lost weight (5.4%) at 75% RH for 7 days. A possible reason for the abnormal hygroscopic behavior is nucleation phenomenon at the interface; that is, a surface change may occur in the presence of water vapor with nucleation by small crystals of the product.

Structure and stereochemistry of brianolide, a new antiinflammatory diterpenoid from the Okinawan gorgonian Briareum sp

Brianolide (1), a new antiinflammatory diterpenoid of the briarein class, possessing a beta substituent at C-12 (R), has been isolated from the Okinawan gorgonian Briareum sp. Its structure has been established from spectral data in conjunction with a single crystal X-ray analysis.

High-resolution solid-state carbon-13 nuclear magnetic resonance spectra of mofebutazone, phenylbutazone, and oxyphenbutazone in relation to X-ray crystallographic data

The solid-state 13C NMR spectra of mofebutazone, phenylbutazone, and oxyphenbutazone monohydrate and anhydrate are presented. The crystal structures of these pyrazolidinedione derivatives, obtained by single-crystal X-ray analysis, were previously reported, revealing distinct differences in crystal structure. In this report, the chemical shift values observed for the solid-state 13C spectra are related to the chemical environment of the various carbon atoms and compared with the crystallographic data. Results indicate that solid-state NMR spectroscopy is potentially useful in the study of drugs in the solid state.

Synthesis and pharmacological evaluation of pyrazolopyrimidobenzoxazole and pyrazolopyrimidobenzothiazole derivatives

As a part of research on polieterocycles compounds with condensed nuclei, containing pyrimidine ring, as potential antalgic/anti-inflammatory drugs, pyrazolopyrimidobenzoxazole and pyrazolopyrimidobenzothiazole were prepared and tested. None of the substances shows significative activities in vivo.

Interaction of pirprofen enantiomers with human serum albumin

The interaction of pirprofen enantiomers with human serum albumin (HSA) was investigated by means of high-performance liquid chromatography (HPLC), circular dichroism (CD), and 1H NMR spectroscopy. HPLC experiments indicated that both pirprofen enantiomers were bound to one class of high-affinity binding sites (n(+) = 1.91 +/- 0.13, K(+) = (4.09 +/- 0.64) x 10(5) M-1, n(-) = 2.07 +/- 0.13, K(-) = (6.56 +/- 1.35) x 10(5) M-1) together with nonspecific binding (n'K'(+) = (1.51 +/- 0.21) x 10(4) M-1, n'K'(-) = (0.88 +/- 0.13) x 10(-4) M-1). Slight stereoselectivity in specific binding was demonstrated by the difference in product n(+)K(+) = (0.77 +/- 0.08) x 10(6) M-1 vs. n(-)K(-) = (1.30 +/- 0.21) x 10(6) M-1, i.e., the ratio n(-)K(-)/n(+)K(+) = 1.7. CD measurements showed changes in the binding sites located on the aromatic amino acid side chains (a small positive band at 315 nm and a pronounced negative extrinsic Cotton effect in the region 250-280 nm). The protein remains, however, in its predominantly alpha-helical conformation. The 1H NMR difference spectra confirmed that both pirprofen enantiomers interacted with HSA specifically, most probably with site II on the albumin molecule.

Anatomical and histological studies of Bupleuri radix

Three kinds of Bupleuri Radix were found in Taiwan. To clarify their origins, histological studies were carried out to identify their internal and external structures. It was found that Bupleuri Radix or "Chai-hu" of Taiwan is derived from roots of the following species" 1, Bupleurum chinense which was imported from China, 2, Bupleurum falcatum var. komarowi a cultivated production of Japanese origin, and 3, Bupleurum kaoi which is indigenous to Taiwan. These Bupleuri Radix were easily assigned by anatomical characteristics and their qualitative analysis of active principle - saikosaponin were established by TLC.

Studies on 1,2,3-triazole derivatives as in vitro inhibitors of prostaglandin synthesis

This paper reports some new structural modifications (branching and lengthening of alkanoic substituent, increase of heterocycle-carboxylate distance) on 1,2,3-triazole derivative 1, a potent in vitro inhibitor of prostaglandin synthesis, and their influence on enzyme activity. Regarding the structural relationship between 1 and Dazoxiben, a selective thromboxane-synthetase inhibitor, the preparation and activity of some Dazoxiben analogs bearing different heterocycles, are also described.

Research on heterocyclic compounds. XXVII. Synthesis and antiinflammatory activity of 2-phenylimidazo[1,2-b]pyridazine-3-carboxylic acids

A group of ethyl esters of 2-phenylimidazo[1,2-b]pyridazine-3-carboxylic acids 3 were obtained by reaction in anhydrous ethanol of some substituted 3-aminopyridazines 1 with ethyl 2-benzoyl-2-bromoacetate 2. The acids 4 obtained via alkaline hydrolysis were tested in vivo for their antiinflammatory, analgesic and ulcerogenic actions and in vitro for their ability to inhibit the prostaglandin biosynthesis. Almost all of the new compounds showed high analgesic activity, whereas the activities exhibited in the other tests were sharply lower. These results are discussed in terms of mechanism of action.

Non-steroidal antiinflammatory agents. Synthesis of novel 2-pyrazolyl-4(3H)-quinazolinones

Four novel series of pyrazolyl-4(3H)-quinazolinones have been prepared through the reaction of 3-aryl-2-hydrazino-4(3H)-quinazolinones with antipyrylazo-derivatives of ethyl acetoacetate, acetylacetone or diethyl malonate. These series of compounds are 3-aryl-2-[1-ethoxycarbonyl-1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H - pyrazol-4-yl)hydrazono-2-propylidene]hydrazino-4(3H)-quinazo linones; 3-aryl-2-[4-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) hydrazono-3-methyl-5-oxo-4,5-dihydro-1H-pyrazol-1-yl]-4(3H)-quinaz olinones; 3-aryl-2-[4-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)azo -3,5- dimethyl-1H-pyrazol-1-yl]-4(3H)-quinazolinones and 3-aryl-2-[4-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) hydrazono-3,5-dioxo-pyrazolidin-2-yl]-4(3H)-quinazolinones. The antiinflammatory activity of some representatives of the prepared compounds was studied.

Penta- and hexadienoic acid derivatives: a novel series of 5-lipoxygenase inhibitors

The synthesis of a series of pentadienoic and hexadienoic acid derivatives is reported. These compounds were tested as inhibitors of 5-lipoxygenase (5 LO) and cyclooxygenase (CO) in vitro and as inhibitors of arachidonic acid (AA) induced ear edema in mice in vivo. Their potency is compared with that of the standard inhibitors nafazatrom, BW 755C, NDGA, KME4, quercetine, and L 652,243. The most potent compound in vivo, diethyl 2-hydroxy-5-(ethylthio)-2(Z),4(Z)-hexadienedioate (20) inhibited AA-induced ear edema when administered topically or orally, with an ED50 value of 0.01 mg/ear and 20 mg/kg, respectively. Among the standard compounds tested, L 652,243 was the most active compound in this test with an ED50 value of 0.01 mg/ear and 1 mg/kg po, but unlike this compound, 20 is a selective inhibitor of 5-LO (IC50 = 2 microM) without any significant activity against CO (IC50 greater than 50 microM). Most of the other compounds in this series are also selective 5-LO inhibitors.

In vitro inhibitors of prostaglandin synthesis: (p-thiosubstituted)-benzyl nitrogen heterocycles

This paper reports the preparation of some (p-thiosubstituted)-benzyl (disulfides, thiols, and ethyl 2-mercaptopropionates) nitrogen heterocycles (1,2,3-triazole, imidazole, pyridine, tetrazole and 1,3,4-oxadiazole) and the evaluation of their inhibitory activity of in vitro prostaglandin synthesis. The mercaptopropionates, isosters of previously studied and very effective oxyderivatives, maintain high enzyme activity which is also present, although to a lower degree, in the corresponding disulfides.

Synthesis and antiinflammatory activity of 2H-tetrazol-2-acetic acids, esters and amides

A series of 5-(pyridyl)-2H-tetrazol-2-acetic acids (16-21), esters (10-15), and amides (22-27) was synthesized in order to investigate the effect of 5-substituents (R1 = 2-, 3- or 4-pyridyl) and alpha-substituents (R2 = H, Me) on anti-inflammatory activity. The point of attachment of the R1-pyridyl substituent influenced potency. The relative potencies in the acetic acid ester, acetic acid and acetamide classes of compounds were 2- and 4- greater than 3-pyr, 2- and 3- greater than 4-pyr, and 4- greater than 2- and 3-pyr, respectively. In the acetic acid ester and acetamide classes, compounds having a R2 hydrogen substituent were generally more potent than corresponding methyl substituted compounds, whereas, in the acetic acid class the reverse applied. The relative order of anti-inflammatory potency was generally amide greater than ester greater than acid. 2-[5-(4-Pyridyl)-2H-tetrazol-2-yl]acetamide (26) was the most effective antiinflammatory agent in the series, reducing inflammation by 53% at 3 and 5 hr after a 25 mg/kg po dose.

Diastereoisomeric derivatization and liquid chromatographic analysis of N-(phenylsulfonyl)-2-phenylglycine aldose reductase inhibitors

A series of (S)- and (R)-N-(phenylsulfonyl)-2-phenylglycines are synthesized as potential inhibitors of the enzyme aldose reductase. In vitro analysis of these compounds reveals that the S-enantiomers are more potent than the corresponding R-enantiomers and that the difference in potencies between enantiomeric pairs is dependent on the nature of the ring substituent. To ensure that the enantioselectivity observed does not reflect varying degrees of racemization during the synthesis of the N-(phenylsulfonyl)-2-phenylglycines, the enantiomeric purity of these products is determined by HPLC after chiral derivatization. Each 2-phenylglycine inhibitor is derivatized with R-alpha-methylbenzylamine, and the resulting diastereomers are analyzed using reversed and normal achiral stationary phases. Reversed-phase methods with C18 or phenyl stationary phases and solvent mixtures of acetonitrile or methanol in water do not provide satisfactory resolution of the diastereomers. However, normal-phase analyses with a silica stationary phase and mixtures of methanol, ethanol, or acetonitrile in chloroform provide good separations with relatively short analysis times. The normal-phase analyses demonstrate that a single diastereomeric amide forms from each N-(phenylsulfonyl)-2-phenylglycine product, establishing that these compounds do not racemize during synthesis.

Non-steroidal antiinflammatory agents. VII. Synthesis and antiinflammatory activity of 5-methyl-10,11-dihydro-5H-pyrrolo [1,2-b] [1,2,5]benzotriazepine-11-acetic acid and its 10-aroyl derivatives

The synthesis of 5-methyl-10,11-dihydro-5H-pyrrolo [1,2-b] [1,2,5]benzotriazepine-11-acetic acid and its 10-aroyl derivatives is reported. Compounds were evaluated for antiinflammatory activity by the carrageenin-induced rat paw edema method. Antinociceptic activity was tested by the hot plate and Randall-Selitto tests. General neuropsychopharmacological effects were also screened. All test compounds showed antiinflammatory effect comparable to that of tolmetin.

Acute toxicity tests of mofezolac (N-22) in mice and rats

Mofezolac (N-22) is a newly developed analgesic and anti-inflammatory agent. The acute toxicities of N-22 were investigated in ICR mice and Wistar rats in oral (p.o.), intraperitoneal (i.p.) and subcutaneous (s.c.) routes. LD50 values of N-22 in mice were 1528 mg/kg (p.o.), 275 mg/kg (i.p.) and 612 mg/kg (s.c.) for males, and 1740 mg/kg (p.o.), 321 mg/kg (i.p.) and 545 mg/kg (s.c.) for females. Those in rats were 920 mg/kg (p.o.), 378 mg/kg (i.p.) and 572 mg/kg (s.c.) for males, and 887 mg/kg (p.o.), 342 mg/kg (i.p.) and 510 mg/kg (s.c.) for females. The sex difference was not clearly observed in mice and rats, but the species difference was observed in p.o. routes. As an initial toxic sign, the hypoactivity was observed in mice and rats of all routes, subsequently, paleness of skin, anemic conjunctiva, emaciation, stupor and/or coma were observed in mice and rats of p.o. and i.p. routes. In rats of those routes, tonic and/or asphyxial convulsion and dyspnea were also observed. In pathological examination of mice and rats, gastrointestinal disorders were observed in p.o. and i.p. routes, and changes of subcutaneous tissue at the injection site were observed in s.c. route.

Optical resolution and absolute configuration of a nonsteroidal antiinflammatory drug, 2-(10,11-dihydro-10-oxodibenzo- [b,f]thiepin-2-yl)propionic acid

The title compound (+/-)-1 (CN-100) was efficiently resolved into a pair of enantiomers by fractional crystallization of the diastereomeric salts of (-)- and (+)-phenylethylamine. The purity of the enantiomers was determined using the chiral cellulose column (CHIRALCEL OJ) which was allowed direct separation of the enantiomers. A separation factor (alpha) of 1.73 was obtained. X-Ray crystallographic analysis of the (+)-isomer [salt of (-)-1-(4-bromophenyl)ethylamine] showed that this enantiomer has S-configuration. Biological studies have shown that only the (+)-isomer has antiinflammatory activity. Racemizaiton of (-)-isomer was carried out by heating its propionic acid solution in the presence of mineral acid, such as HBr.