(1/2765) Isolation of SMTP-3, 4, 5 and -6, novel analogs of staplabin, and their effects on plasminogen activation and fibrinolysis.
Four novel triprenyl phenol metabolites, designated SMTP-3, -4, -5, and -6, have been isolated from cultures of Stachybotrys microspora IFO 30018 by solvent extraction and successive chromatographic fractionation using silica gel and silica ODS columns. A combination of spectroscopic analyses showed that SMTP-3, -4, -5, and -6 are staplabin analogs, containing a serine, a phenylalanine, a leucine or a tryptophan moiety in respective molecules in place of the N-carboxybutyl portion of the staplabin molecule. SMTP-4, -5, and -6 were active at 0.15 to 0.3 mM in enhancing urokinase-catalyzed plasminogen activation and plasminogen binding to fibrin, as well as plasminogen- and urokinase-mediated fibrinolysis. On the other hand, the concentration of staplabin required to exert such effects was 0.4 to 0.6 mM, and SMTP-3 was inactive at concentrations up to 0.45 mM. (+info)
(2/2765) Novel selective inhibitors for human topoisomerase I, BM2419-1 and -2 derived from saintopin.
Compounds BM2419-1 and -2 were isolated from a culture broth of a fungus Paecilomyces sp. BM2419. It was shown that these novel compounds were artifacts derived from saintopin, a dual inhibitor of topoisomerase I and II by independent processes. In the human topoisomerase I inhibition assay using the recombinant Saccharomyces cerevisiae, BM2419-1 and -2 inhibited selectively the yeast growth dependent on human topoisomerase I induction with IC50 values of 0.3 ng/ml and 6.0 ng/ml, respectively. (+info)
(3/2765) Apicularens A and B, new cytostatic macrolides from Chondromyces species (myxobacteria): production, physico-chemical and biological properties.
A novel macrolide, apicularen A, was produced by several species of the genus Chondromyces. Initially it was discovered by bioassay-guided RP-HPLC-fractionation of culture extracts of Chondromyces robustus, strain Cm a13. Apicularen A showed no antimicrobial activity, but was highly cytotoxic for cultivated human and animal cells, with IC50 values ranging between 0.1 and 3 ng/ml. A cometabolite of apicularen A, the N-acetylglucosamine glycoside apicularen B, was distinctly less cytotoxic with IC50 values between 0.2 and 1.2 microg/ml, and showed weak activity against a few Gram-positive bacteria. Apicularen A is chemically closely related to the salicylihalamides A and B from the marine sponge Haliclona sp. (+info)
(4/2765) BE-31405, a new antifungal antibiotic produced by Penicillium minioluteum. I. Description of producing organism, fermentation, isolation, physico-chemical and biological properties.
A new antifungal antibiotic, BE-31405, was isolated from the culture broth of a fungal strain, Penicillium minioluteum F31405. BE-31405 was isolated by adsorption on high porous polymer resin (Diaion HP-20), followed by solvent extraction, precipitation and crystallization. BE-31405 showed potent growth inhibitory activity against pathogenic fungal strains such as Candida albicans, Candida glabrata and Cryptococcus neoformans, but did not show cytotoxic activity against mammalian cells such as P388 mouse leukemia. The mechanism studies indicated that BE-31405 inhibited the protein synthesis of C. albicans but not of mammalian cells. (+info)
(5/2765) Diperamycin, a new antimicrobial antibiotic produced by Streptomyces griseoaurantiacus MK393-AF2. I. Taxonomy, fermentation, isolation, physico-chemical properties and biological activities.
Antibacterial antibiotics, diperamycin (1) was produced in the culture broth of Streptomyces griseoaurantiacus MK393-AF2. Various spectroscopic analyses of 1 suggested that 1 belonged to a member of cyclic hexadepsipeptide antibiotic. Antibiotic 1 had potent inhibitory activity against various Gram-positive bacteria including Enterococcus seriolicida and methicillin-resistant Staphylococcus aureus. (+info)
(6/2765) Structure of actinotetraose hexatiglate, a unique glucotetraose from an actinomycete bacterium.
An Actinomycete strain A499 belonging to the genera Amycolatopsis or Amycolata isolated from a Western Australian soil sample produced the cyclic decapeptide antibiotic quinaldopeptin (1), together with the actinotetraose hexatiglate (2), the hexa-ester of a novel non-reducing glucotetraose. (+info)
(7/2765) Relationships between the lipophilicity of some 1,4-piperazine derivatives of aryloxyaminopropanols and their beta-andrenolytic activity.
Nineteen 1,4-piperazine derivatives of aryloxyaminopropanol were evaluated with respect to beta-adrenolytic activity. The retention factors obtained from HPLC, RM values obtained from partition TLC and the lipophilic Hansch's (4) constants pi were determined and the compounds were studied with respect to their lipophilicity based on chromatographic properties. The study of the influence of different substituents introduced at the para position on the phenyl ring on the retention factor indicated the log k vs. the number of carbon atoms in R1 substituent to be a linear relationship. Attempts have been made to relate the beta-adrenolytic activity to the lipohydrophilic parameters by deriving a quantitative relationship between them. Significant parabolic correlation was observed between the beta-adrenolytic activity and the logarithm of the retention factor, log k. An analogous relationship was obtained between the beta-adrenolytic activity of the compounds and the RM values obtained from partition TLC as well as Hansch's lipophilic constants pi. (+info)
(8/2765) Determination of the lipophilicity of active anticonvulsant N-substituted amides of alpha-arylalkylamine-gamma-hydroxybutyric acid.
The lipophilicities of fourteen anticonvulsant active N-substituted amides of alpha-arylalkylamine-gamma-hydroxybutyric acid [I-XIV] have been determined by reversed-phase thin-layer chromatography with a mixture of methanol, TRIS buffer, and acetic acid as the solvent system. The RM value of each compound decreased linearly with increasing concentration of methanol. The partition coefficients (log P) of the amides were calculated by use of the Prolog P module of the Pallas system. Comparison of RM and log P enabled clog P values to be calculated. It was found that the anticonvulsant activity of amides [I-XIV] can be explained on the basis of their lipophilicity. (+info)