New glutarimide antibiotics, S-632-B1 and B2. I. Taxonomy of producing strain, fermentation and biological properties.

Strain S-632 was found to produce new glutarimide antibiotics, S-632-B1 and B2, which were isolated from the culture fluid. A taxonomic study on strain S-632 was carried out, and the taxonomic characterization demonstrated that it belonged to the species Streptomyces hygroscopicus. The strain was given the name S. hygroscopicus S-632. These antibiotics were active against Saccharomyces sp., but inactive against filamentous fungi and bacteria, and had cytotoxic activity against KB tissue culture cells.

New glutarimide antibiotics, S-632-B1 and B2. II. Isolation, physico-chemical properties and chemical structure.

Antifungal antibiotics S-632-A1,A2,B1 and B2 were extracted with ethyl acetate from the filtered broth of Streptomyces hygroscopicus S-632 and isolated through a combination of conventional and reversed-phase silica gel column chromatography. On the basis of the spectral data, S-632-B1 and B2 were found to be new members of the glutarimide family of antibiotics. The chemical structures of these components were elucidated as two stereo-isomers of 3-(5,7-dimethyl-8,9-epoxy-2-hydroxy-4-oxo-6-decenyl)glutarimide.

High-performance liquid chromatographic determination of 6-amidino-2-naphthyl [4-(4,5-dihydro-1H-imidazol-2-yl) amino]benzoate dimethanesulphonate and its metabolites in biological fluids.

6-Amidino-2-naphthyl [4-(4,5-dihydro-1H-imidazol-2-yl) amino]benzoate dimethanesulphonate has been developed for the therapy of pancreatitis. A reversed-phase high-performance liquid chromatographic assay of the levels of this drug and its metabolites in biological fluids was investigated. Fluorescence detection with post-column alkaline degradation was used for the determination of the intact drug and the amidinonaphthol moiety metabolite, and ultraviolet detection at 254 nm was used to determine the levels of the benzoic acid moiety metabolite. Satisfactory recoveries and variabilities of the intact drug and its metabolites from biological fluids were obtained. The detection limits for the intact drug and amidinonaphthol were 0.5 ng/ml at a signal-to-noise ratio of 12 in plasma and 10 ng/ml at a signal-to-noise ratio of 32 in urine and homogenized faeces, and those of benzoic acid were 5 ng/ml at a signal-to-noise ratio of 3 in plasma and 50 ng/ml at a signal-to-noise ratio of 7 in urine and homogenized faeces.

Gas chromatographic-negative-ion chemical ionization mass spectrometric determination of a new dihydropyridine calcium antagonist (MPC-1304) and its metabolites in human plasma and urine.

A gas chromatographic-negative-ion chemical ionization mass spectrometric method was developed for the determination of a new calcium antagonist, (+/-)-methyl 2-oxopropyl 1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl)-3,5-pyridinedicarboxylate, and its metabolites in plasma and urine. The sample was extracted with n-hexane-diethyl ether. The dried organic layer was subjected to acetylation: the aqueous layer was acidified and extracted with ethyl acetate, and after the ethyl acetate extract was dried the resulting residue was subjected to methylation. Aliquots of each reactant solution were injected into the gas chromatograph-mass spectrometer, equipped with a chemical ionization source and negative-ion monitoring mode, and analysed by the selected-ion monitoring method using deuterium-labelled internal standards. Detection was limited to 0.02-0.05 ng/ml of plasma and urine for each metabolite. A precise and sensitive assay for the determination of a new dihydropyridine calcium antagonist and its metabolites in plasma and urine was thus established.

A new macromolecular antitumor antibiotic, C-1027. II. Isolation and physico-chemical properties.

A new macromolecular antibiotic C-1027 was obtained from the broth filtrate of Streptomyces globisporus C-1027 by precipitation with ammonium sulfate, DEAE-cellulose column chromatography and gel filtration chromatography on a Sephadex G-75 column. This antibiotic, prepared as a white powder, is an acidic polypeptide having an isoelectric point of pH 3.5-3.7 and a molecular weight of 15,000 as determined by SDS-polyacrylamide gel electrophoresis and gel filtration chromatography. The acid hydrolysate of the purified antibiotic C-1027 contained no methionine or tryptophan. From the physico-chemical data, it may be considered to possess a very labile non-protein chromophore.

A new macromolecular antitumor antibiotic, C-1027. I. Discovery, taxonomy of producing organism, fermentation and biological activity.

Strain C-1027, an actinomycete isolated from a soil sample collected in China, was found to produce the new antibiotic, C-1027. From taxonomical studies on its morphological, cultural and physiological characteristics, this antibiotic-producing strain was identified as Streptomyces globisporus C-1027. Antibiotic C-1027 has antimicrobial activity against most Gram-positive bacteria but not against Mycobacterium sp. or Gram-negative bacteria. This antibiotic shows remarkable activity in spermatogonial assay and potent cytotoxicity against KB carcinoma cells in vitro, and exhibits inhibition on transplantable tumors in mice.

High-performance liquid chromatographic determination of a new beta-lactamase inhibitor and its metabolite in combination therapy with piperacillin in biological materials.

[2S-(2 alpha,3 beta,5 alpha)]-3-Methyl-7-oxo-3-(1H-1,2,3-triazol-1-yl- methyl)-4-thia-1-azabicyclo [3.2.0]-heptane-2-carboxylic acid 4,4-dioxide (YTR-830H) is a new beta-lactamase inhibitor and the combination therapy of this compound with piperacillin is now under study. For the determination of the beta-lactamase inhibitor and piperacillin in biological materials, plasma and visceral tissue homogenates were deproteinized, whereas diluted urine and filtered faeces homogenates were treated with a Sep-Pak C18 cartridge. In order to assay the inactive metabolite of beta-lactamase inhibitor, each sample was treated with a Sep-Pak C18 cartridge. Aliquots of each preparation were chromatographed using ion-pair and reversed-phase chromatographic techniques on a high-performance liquid chromatograph equipped with a UV detector, set at 220 nm. The detection limits of beta-lactamase inhibitor and piperacillin were 0.2 microgram/ml in plasma, 2.5-5.0 micrograms/ml in urine and 0.2-0.5 microgram/g in visceral tissue and faeces. Those of the metabolite were 1.0 microgram/ml in plasma, 2.5-5.0 micrograms/ml in urine and 1.0 microgram/g in visceral tissue and faeces. A precise and sensitive assay for the determination of the beta-lactamase inhibitor, its metabolite and piperacillin is described, and their stabilities in several media are reported.

New antibiotics 4181-A and B from Streptomyces griseus; taxonomy, fermentation, isolation and characterization.

The new antibiotics 4181-A and B were isolated from the fermentation broth of Streptomyces griseus, a soil isolate. Their molecular formulae were determined as C29H21NO9 and C28H19NO9, respectively. The UV, IR and NMR spectra suggest that they possess a quinone moiety in their structures. They were found to have antibacterial, antifungal and antitumor activity.

High-performance of liquid chromatographic determination of [3,4-di-(4-methoxyphenyl)-5-isoxazolyl]acetic acid and its metabolites in human plasma and urine.

A high-performance liquid chromatographic method is described for the simultaneous determination of the non-steroidal analgesic and anti-inflammatory agent [3,4-di-(4-methoxyphenyl)-5-isoxazolyl]acetic acid and its three metabolites in plasma and urine. Deproteinized plasma (with acetonitrile) or urine was applied to a Sep-Pak C18 cartridge, washed with distilled water and then eluted with methanol. The methanol eluate was reduced to dryness. The resulting residues from the plasma and urine were redissolved in methanol aqueous solution, respectively. Aliquots of each solution were chromatographed on a reversed-phase column using a mobile phase of methanol-20 mM potassium dihydrogenphosphate (pH 6.4) (linear gradient from 0 to 100% methanol at 3%/min with a flow-rate of 1.5 ml/min) on a liquid chromatograph equipped with an ultraviolet absorbance detector (254 nm). Detection was limited to 10 ng/ml in plasma and 100 ng/ml in urine for each compound. An accurate and sensitive assay for the determination of [3,4-di-(4-methoxyphenyl)-5-isoxazolyl]acetic acid and its metabolites was established.

Determination of cefodizime in biological materials by high-performance liquid chromatography.

Cefodizime (THR-221) is a new semi-synthetic cephalosporin. A high-performance liquid chromatographic method has been developed for the determination of cefodizime in biological materials. A plasma or serum sample was deproteinized with methanol and the resulting methanol eluate was concentrated to a volume of 0.5 ml. Urine and bile samples were diluted with buffer and each diluted sample was filtered. Faeces samples were homogenized and the supernate obtained after centrifugation was filtered. Visceral tissue samples were homogenized, the centrifuged supernate was deproteinized with methanol, and the methanol eluate was concentrated to a volume of 0.5 ml. Aliquots of each preparation were chromatographed on a reversed-phase column with an ion-pair chromatographic technique on a high-performance liquid chromatograph equipped with an UV detector set at 264 nm. The detection limits for cefodizime were 0.1 microgram/ml in plasma or serum, 0.3 microgram/ml in bile, and 0.5 microgram/ml in urine, 0.5 microgram/g in faeces and visceral tissue. This precise and sensitive assay for the determination of cefodizime is described, and its stability in several media is reported.

Gas chromatographic-mass fragmentographic determination of propiverine and its metabolites in plasma and urine.

1-Methyl-4-piperidyl diphenylpropoxyacetate hydrochloride has been developed clinically for the therapy of urinary bladder dysfunction. A gas chromatographic-mass fragmentographic method was developed for the determination of this drug and its seven metabolites in plasma and urine. The sample was first treated with a Sep-Pak C18 cartridge, the methanol eluate was evaporated to dryness, and the resulting residue was redissolved in distilled water. This solution was then extracted with chloroform and adjusted to pH 9.0 with 0.1 M sodium borate solution. The acidified aqueous layers were extracted with ethyl acetate. The chloroform layer, which contained non-polar metabolites, was concentrated to dryness, then subjected to trifluoroacetylation, decomposition and methylation. The extract from the plasma sample was trimethylsilylated. The dried residue of the ethyl acetate layer, which contained polar metabolites, was subjected to methylation, trifluoroacetylation and decomposition. Aliquots of each reactant solution were injected into the gas chromatograph-mass spectrometer and analysed by the selected-ion monitoring method using an internal standard. Detection was limited to 1-2 ng/ml of plasma and urine for each metabolite. A precise and sensitive assay for the determination of 1-methyl-4-piperidyl diphenylpropoxyacetate hydrochloride and its metabolites in plasma and urine was thus established, and it should prove useful in basic and clinical pharmacological studies.

Cytochrome P-450-dependent oxidative cleavage of 1-(tetrahydro-2-furanyl)-5-fluorouracil to 5-fluorouracil.

Cytochrome P-450-dependent oxidative cleavage of 1-(tetrahydro-2-furanyl)-5-fluorouracil (FT) was investigated in a reconstituted system containing purified phenobarbital-inducible cytochrome P-450 (P-450(1)) or 3-methylcholanthrene-inducible cytochrome P-450 (P-448(1)). FT was converted into 5-fluorouracil (5-FU) in the reconstituted system, and its rate was 71 pmol 5-FU formed/min/nmol P-4501 and 45 pmol 5-FU/min/nmol P-448(1). Cytochrome P-450, NADPH-cytochrome P-450 reductase and NADPH were required for 5-FU production. Inhibitors of cytochrome P-450 such as carbon monoxide and metyrapone markedly decreased the rate. FT was found to interact with the purified cytochrome P-450, causing a reverse type I spectral change. From these observations, we concluded that the hepatic microsomal cytochrome P-450-dependent mixed function oxidase system participates in the oxidative cleavage of FT.

GLC-mass fragmentographic determination of mannitol and sorbitol in plasma.

A GLC-mass fragmentographic method was developed for the simultaneous determination of mannitol and sorbitol as their n-butyldiboronate derivatives in plasma. The plasma sample was deproteinized, and the subsequent supernatant was concentrated to dryness; the resulting residue was then dissolved in pyridine containing n-butylboronic acid to allow derivation. An aliquot of this solution was injected into the gas chromatograph-mass spectrometer and analyzed by a selected-ion monitoring method using galactitol as the internal standard. Detection was limited to 20 ng/0.1 ml of plasma for both mannitol and sorbitol. A rapid, precise, and sensitive assay for the determination of mannitol and sorbitol in plasma was established.

High-performance liquid chromatographic determination of proglumide in plasma.

A rapid and sensitive method for determining the anticholinergic agent, proglumide, in plasma by high-performance liquid chromatography is described. Samples were acidified with hydrochloric acid and extracted with chloroform. The dried extract was resolved in chloroform and chromatographed on an adsorption chromatographic column using a mobile phase of chloroform-methanol (24:1) on a high-performance liquid chromatograph equipped with a UV absorbance detector (240 nm). The detection limit for proglumide was 0.05 microgram/ml.