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The concise syntheses of (-)-habiterpenol and (+)-2,3- epi -habiterpenol from (3a R )-(+)-sclareolide and 6-methoxyindanone in 11 and 12 steps, respectively, were enabled by the regioselective addition of the TMS-indenyl anion and the facile stereoselective metal hydride hydrogen atom transfer (MHAT)-initiated redox radical cyclization of alkenylsilane.

Habiterpenol is a G2 checkpoint inhibitor isolated from the culture broth of Phytohabitans sp. 3787_5. Here, we report the synthesis of new habiterpenol analogs through the total synthesis process of habiterpenol and evaluating the analogs for G2 checkpoint inhibitory activity. We investigated two different synthetic approaches for total synthesis, with intramolecular conjugate addition and Ti(III)-mediated radical cyclization as key reactions. Although the former was unsuccessful, the latter reaction facilitated stereoselective total synthesis and determination of the absolute configuration of habiterpenol. The extension of these chemistries to a structure-activity relationship (SAR) study gave new habiterpenol analogs, which could not be derived from natural habiterpenol and only be synthesized by applying the total synthesis. Therefore, this study provides important insights into SAR studies of habiterpenol.

Research on natural product chemistry via organic chemistry ranges from isolation and structural elucidation to total synthesis, drug discovery, and chemical biology. Discoveries in organic chemistry, such as novel reactions and synthetic strategies, are enabled by the studies of total synthesis. Thus, organic (synthetic) chemistry and natural product chemistry are correlated. We conducted comprehensive studies, including structure-activity relationship, drug discovery, and total synthesis studies, on the synthetic organic chemistry of natural products with unique biological activities and the development of novel reactions discovered through these products. This review describes the total synthesis of simpotentin, a novel potentiator of amphotericin B, and the development of the novel lactonization reactions of homopropargyl alcohols via intramolecular ketene trapping.

Background: In clinical practice, a mixed suspension of clopidogrel bisulfate and magnesium oxide (MgO) tablets is administered frequently via a feeding tube. However, there is no report on the changes occurring when suspensions of these two drugs are combined, including the effects or potential decrease in dose following tube administration. Thus, the purpose of our study was to investigate the (i) changes caused by mixing clopidogrel bisulfate (ion form) and MgO tablets and (ii) effects on the administered clopidogrel dose after passing through a feeding tube., Methods: The molecular structure of clopidogrel generated in a mixture of clopidogrel bisulfate and a basic compound, such as sodium bicarbonate or MgO tablet, was determined by 1 H-NMR after extraction and purification. The suspension of clopidogrel bisulfate tablet alone and the mixed suspension of clopidogrel bisulfate tablet and MgO tablet were passed through a feeding tube. We compared the yield of the molecular form of clopidogrel from each passed fraction., Results: The substance obtained from the mixture of clopidogrel bisulfate tablet and sodium bicarbonate or MgO tablet was identified as the molecular form of clopidogrel, and chemical degradation did not occur under these conditions. In the tube passage test, the yield of clopidogrel (molecular form) from the mixture of clopidogrel bisulfate and MgO tablets was lower than that from the suspension of clopidogrel bisulfate tablet alone., Conclusions: The mixture of clopidogrel bisulfate and MgO tablets caused a considerable reduction in the administered dose passed through the feeding tube. Therefore, it is recommended to administer the suspensions of clopidogrel bisulfate and MgO tablets separately for safe and effective pharmacotherapy.

A one-pot γ-lactonization of homopropargyl alcohols via an alkyne deprotonation/boronation/oxidation sequence has been developed. Oxidation of the generated alkynyl boronate affords the corresponding ketene intermediate, which is trapped by the adjacent hydroxy group to furnish the γ-lactone. We have optimized the conditions as well as examined the substrate scope and synthetic applications of this efficient one-pot lactonization.

Here we interrogate the structurally dense (1.64 mcbits/Å 3 ) GABA A receptor antagonist bilobalide, intermediates en route to its synthesis, and related mechanistic questions. 13 C isotope labeling identifies an unexpected bromine migration en route to an α-selective, catalytic asymmetric Reformatsky reaction, ruling out an asymmetric allylation pathway. Experiment and computation converge on the driving forces behind two surprising observations. First, an oxetane acetal persists in concentrated mineral acid (1.5 M DCl in THF- d 8 /D 2 O); its longevity is correlated to destabilizing steric clash between substituents upon ring-opening. Second, a regioselective oxidation of des -hydroxybilobalide is found to rely on lactone acidification through lone-pair delocalization, which leads to extremely rapid intermolecular enolate equilibration. We also establish equivalent effects of (-)-bilobalide and the nonconvulsive sesquiterpene (-)-jiadifenolide on action potential-independent inhibitory currents at GABAergic synapses, using (+)-bilobalide as a negative control. The high information density of bilobalide distinguishes it from other scaffolds and may characterize natural product (NP) space more generally. Therefore, we also include a Python script to quickly (ca. 132 000 molecules/min) calculate information content (Böttcher scores), which may prove helpful to identify important features of NP space.

Purpose: We postulate that the deoxyguanosine analogue CNDAG [9-(2-C-cyano-2-deoxy-1-β-D-arabino-pentofuranosyl)guanine] likely causes a single-strand break after incorporation into DNA, similar to the action of its cytosine congener CNDAC, and that subsequent DNA replication across the unrepaired nick would generate a double-strand break. This study aimed at identifying cellular responses and repair mechanisms for CNDAG prodrugs, 2-amino-9-(2-C-cyano-2-deoxy-1-β-D-arabino-pentofuranosyl)-6-methoxy purine (6-OMe) and 9-(2-C-cyano-2-deoxy-1-β-D-arabino-pentofuranosyl)-2,6-diaminopurine (6-NH 2 ). Each compound is a substrate for adenosine deaminase, the action of which generates CNDAG., Methods: Growth inhibition assay, clonogenic survival assay, immunoblotting, and cytogenetic analyses (chromosomal aberrations and sister chromatid exchanges) were used to investigate the impact of CNDAG on cell lines., Results: The 6-NH 2 derivative was selectively potent in T cell malignant cell lines. Both prodrugs caused increased phosphorylation of ATM and its downstream substrates Chk1, Chk2, SMC1, NBS1, and H2AX, indicating activation of ATM-dependent DNA damage response pathways. In contrast, there was no increase in phosphorylation of DNA-PKcs, which participates in repair of double-strand breaks by non-homologous end-joining. Deficiency in ATM, RAD51D, XRCC3, BRCA2, and XPF, but not DNA-PK or p53, conferred significant clonogenic sensitivity to CNDAG or the prodrugs. Moreover, hamster cells lacking XPF acquired remarkably more chromosomal aberrations after incubation for two cell cycle times with CNDAG 6-NH 2 , compared to the wild type. Furthermore, CNDAG 6-NH 2 induced greater levels of sister chromatid exchanges in wild-type cells exposed for two cycles than those for one cycle, consistent with increased double-strand breaks after a second S phase., Conclusion: CNDAG-induced double-strand breaks are repaired mainly through homologous recombination.

The Ginkgo biloba metabolite bilobalide is widely ingested by humans but its effect on the mammalian central nervous system is not fully understood 1-4 . Antagonism of γ-aminobutyric acid A receptors (GABA A Rs) by bilobalide has been linked to the rescue of cognitive deficits in mouse models of Down syndrome 5 . A lack of convulsant activity coupled with neuroprotective effects have led some to postulate an alternative, unidentified target 4 ; however, steric congestion and the instability of bilobalide 1,2,6 have prevented pull-down of biological targets other than the GABA Α Rs. A concise and flexible synthesis of bilobalide would facilitate the development of probes for the identification of potential new targets, analogues with differential selectivity between insect and human GABA Α Rs, and stabilized analogues with an enhanced serum half-life 7 . Here we exploit the unusual reactivity of bilobalide to enable a late-stage deep oxidation that symmetrizes the molecular core and enables oxidation states to be embedded in the starting materials. The same overall strategy may be applicable to G. biloba congeners, including the ginkgolides-some of which are glycine-receptor-selective antagonists 8 . A chemical synthesis of bilobalide should facilitate the investigation of its biological effects and its therapeutic potential.

The total synthesis of simpotentin ( 1 ), a new potentiator of amphotericin B activity against Candida albicans , was achieved. Our research results enabled the access of all stereoisomers of 1 and the elucidation of the unknown absolute configuration of 1 . Furthermore, one of the stereoisomers is a better amphotericin B potentiator than 1 and is an excellent lead compound for the development of a novel amphotericin B potentiator.

The 'neurotrophic sesquiterpenes' refer to a group of molecules derived from the Illicium genus of flowering plant. They display neurotrophic effects in cultured neuron preparations and have been suggested to be cognitive enhancers and potential therapeutics for neurodegenerative disorders and dementias. Recent synthetic advances generated sufficient quantities of jiadifenolide for in vivo investigation into its biological effects. Jiadifenolide did not induce convulsions in mice nor did it enhance or diminish convulsions induced by pentylenetetrazole. Other negative allosteric modulators of GABA A receptors, picrotoxin, tetramethylenedisulfotetramine (TETS), and bilobalide all induced convulsions. Either i.p. or i.c.v. dosing generated micromolar plasma and brain levels of jiadifenolide but only small effects on locomotion of mice. However, jiadifenolide decreased d-amphetamine-induced hyperlocomotion in mice, an antipsychotic-like drug effect. Jiadifenolide did not significantly alter body temperature or behavior in the forced-swim test in mice. Molecular simulation data suggested a potential site in the pore/M2 helix region that is at an overlapping, yet lower position than those observed for other 'cage convulsant' compounds such as TETS and picrotoxin. We hypothesize that a position nearer to the entrance of the pore channel may allow for easier displacement of jiadifenolide from its blocking location leading to lower potency and lower side-effect liability. Like jiadifenolide, memantine (Namenda), one of the few drugs used in the symptomatic treatment of dementias, occupies a unique site on the NMDA receptor complex that creates low binding affinity that is associated with its reduced side-effect profile. Given the potential therapeutic applications of jiadifenolide and its relatively inert effects on overt behavior, the possibility of clinical utility for jiadifenolide and related compounds becomes intriguing., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Currently, pyripyropene A, which is isolated from the culture broth of Aspergillus fumigatus FO-1289, is the only compound known to strongly and selectively inhibit the isozyme sterol O-acyltransferase 2 (SOAT2). To aid in the development of new cholesterol-lowering or anti-atherosclerotic agents, new A-ring simplified pyripyropene A analogues have been designed and synthesized based on total synthesis, and the results of structure-activity relationship studies of pyripyropene A. Among the analogues, two A-ring simplified pyripyropene A analogues exhibited equally efficient SOAT2 inhibitory activity to that of natural pyripyropene A. These new analogues are the most potent and selective SOAT2 inhibitors to be used as synthetic compounds and attractive seed compounds for the development of drug for dyslipidemia, including atherosclerotic disease and steatosis., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Three new compounds, designated scopranones A-C, were isolated from the culture broth of a soil isolate, Streptomyces sp. BYK-11038, and shown to be inhibitors of bone morphogenetic protein (BMP) induced alkaline phosphatase activity in a BMP receptor mutant cell line. The structures were elucidated using NMR and other spectral data. The scopranones have an unusual structure with two atypical scooplike moieties linked at the tails to form part of a unique 3-furanone ring.

11-O-Debenzoyltashironin (1) is a member of the neurotrophic sesquiterpenes, trace plant metabolites that enhance neurite outgrowth in cultured neurons. We report its synthesis in six steps from a butenolide heterodimer via its likely biosynthetic precursor, 3,6-dideoxy-10-hydroxypseudoanisatin, here identified as the chain tautomer of 1. Access to the tashironin chemotype fills a gap in a comparison set of convulsive and neurotrophic sesquiterpenes, which we hypothesized to share a common target. Here we show that both classes mutually hyperexcite rat cortical neurons, consistent with antagonism of inhibitory channels and a mechanism of depolarization-induced neurite outgrowth.

Nafuredin-γ, obtained from natural nafuredin, has demonstrated a potent and selective inhibitory activity against nematode complex I. However, nafuredin-γ is unstable in air since its conjugated dienes are oxygen-labile. The instability in air was naturally solved by the synthesis of structure-simplified nafuredin-γ analogs without conjugated dienes. However, these modified analogs showed lower complex I inhibitory activities. Therefore, new air-stable structure-simplified nafuredin-γ analogs were designed and synthesized herein. Among all analogs synthesized, the one bearing a unique 1-azabicyclo[3.1.0]hexane scaffold showed the highest inhibitory activity (IC 50 =170 nM) while presenting high selectivity against nematode complex I.

The targets of antifungal antibiotics in clinical use are more limited than those of antibacterial antibiotics. Therefore, new antifungal antibiotics with different mechanisms of action are desired. In the course of our screening for antifungal antibiotics of microbial origins, new antifungal antibiotics, simplifungin (1) and valsafungins A (2) and B (3), were isolated from cultures of the fungal strains Simplicillium minatense FKI-4981 and Valsaceae sp. FKH-53, respectively. The structures of 1 to 3 including their absolute stereochemistries were elucidated using various spectral analyses including NMR and collision-induced dissociation (CID)-MS/MS as well as chemical approaches including modifications to the Mosher's method. They were structurally related to myriocin. They inhibited the growth of yeast-like and zygomycetous fungi with MICs ranging between 0.125 and 8.0 μg/mL. An examination of their mechanisms of action by the newly established assay using LC-MS revealed that 1 and 2 inhibited serine palmitoyltransferase activity, which is involved in sphingolipid biosynthesis, with IC50 values of 224 and 24 nM, respectively.

Cyslabdan was isolated from the culture broth of Streptomyces sp. K04-0144 as a new potentiator of imipenem activity against methicillin-resistant Staphylococcus aureus. We accomplished the synthesis of cyslabdan according to a previously reported structure. However, we subsequently found that this structure was incorrect; our analysis of natural cyslabdan showed that it possessed R stereochemistry at the C8 position, not S, as had previously been reported. Thus, we completed the protecting-group-free synthesis of the correct structure of cyslabdan, which is described herein.

Sterol O-acyltransferase 2 (SOAT2; also known as ACAT2) is considered as a new therapeutic target for the treatment or prevention of hypercholesterolemia and atherosclerosis. Fungal pyripyropene A (PPPA: 1,7,11-triacyl type), the first SOAT2-selective inhibitor, proved orally active in vivo using atherogenic mouse models. The purpose of the present study was to demonstrate that the PPPA derivatives (PRDs) prove more effective in the mouse models than PPPA. Among 196 semisynthetic PPPA derivatives, potent, SOAT2-selective, and stable PRDs were selected. In vivo antiatherosclerotic activity of selected PRDs was tested in apolipoprotein E knockout (Apoe(-/-)) mice or low-density lipoprotein receptor knockout (Ldlr(-/-)) mice fed a cholesterol-enriched diet (0.2% cholesterol and 21% fat) for 12 weeks. During the PRD treatments, no detrimental side effects were observed. Among three PRDs, Apoe(-/-) mice treated with PRD125 (1-,11-O-benzylidene type) at 1 mg/kg/day had significantly lower total plasma cholesterol concentration by 57.9 ± 9.3%; further, the ratio of cholesteryl oleate to cholesteryl linoleate in low-density lipoprotein was lower by 55.6 ± 7.5%, respectively. The hepatic cholesteryl ester levels and SOAT2 activity in the small intestines and livers of the PRD-treated mice were selectively lowered. The atherosclerotic lesion areas in the aortae of PRD125-treated mice were significantly lower at 62.2 ± 13.1%, respectively. Furthermore, both PRDs were also orally active in atherogenic Ldlr(-/-) mice. Among the PRDs tested, PRD125 was the most potent in both mouse models. These results suggest that SOAT2-selective inhibitors such as PRD125 have a high potential as poststatin agents for treatment and/or prevention in patients with atherosclerosis and hypercholesterolemia., (Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.)

Nafuredin-γ (2), converted from nafuredin (1) under mild basic conditions, demonstrates potent and selective inhibitory activity against helminth complex I. However, 2 is unstable in air because the conjugated dienes are oxygen-labile. To address this, we designed and synthesized air-stable nafuredin-γ analogs. Although the complex I inhibitory activities of all the new nafuredin-γ analogs were lower than that of 2, all were in the high nM range (IC50: 300-820nM)., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

5-(4'-Methoxyphenyl)-oxazole (MPO), originally reported as a synthetic compound, was isolated from fungal culture broth as an inhibitor of hatch and growth of Caenorhabditis elegans. Nineteen MPO derivatives were chemically synthesized, but showed no effect on C. elegans hatch and growth. These findings strongly suggested that the whole structure of MPO is essential for anti-C. elegans activity., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Pyripyropene A (PPPA, 1) of fungal origin, a selective inhibitor of acyl-CoA:cholesterol acyltransferase 2 (ACAT2), proved orally active in atherogenic mouse models. The in vitro metabolites of 1 in liver microsomes and plasma of human, rabbit, rat and mouse were analyzed by ultra fast liquid chromatography and liquid chromatography/tandem mass spectrometry. In the liver microsomes from all species, successive hydrolysis occurred at the 1-O-acetyl residue, then at the 11-O-acetyl residue of 1, while the 7-O-acetyl residue was resistant to hydrolysis. Furthermore, dehydrogenation of the newly generated 11-alcoholic hydroxyl residue occurred in human and mouse-liver microsomes, while oxidation of the pyridine ring occurred in human and rabbit liver microsomes. On the other hand, hydrolysis of the 7-O-acetyl residue proceeded only in the mouse plasma. These data indicated that the in vitro metabolic profiles of 1 have subtle differences among animal species. All of the PPPA metabolites observed in liver microsomes and plasma markedly decreased ACAT2 inhibitory activity. These findings will help us to synthesize new PPPA derivatives more effective in in vivo study than 1.

In an effort to develop potent and selective inhibitors toward ACAT2, structure-activity relationship studies were carried out using derivatives based on pyripyropene A (PPPA, 1). In particular, we investigated the possibility of introducing appropriate 1,11-O-benzylidene and 7-O-substituted benzoyl moieties into PPPA (1). The new o-substituted benzylidene derivatives showed higher selectivity for ACAT2 than PPPA (1). Among them, 1,11-O-o-methylbenzylidene-7-O-p-cyanobenzoyl PPPA derivative 7q and 1,11-O-o,o-dimethylbenzylidene-7-O-p-cyanobenzoyl PPPA derivative 7z proved to be potent ACAT2 inhibitors with unprecedented high isozyme selectivity., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Synthesis and structure-activity relationships of 7-O-p-cyanobenzoyl pyripyropene A derivatives with modification at C1 and 11 are described. Regioselective mono-deprotection of di-tert-butylsilylene acetal was critical in their synthesis., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

In an effort to develop potent and selective inhibitors toward ACAT2, structure-activity relationship studies were carried out using derivatives based on pyripyropene A (PPPA, 1). We have successfully developed novel PPPA derivatives with a 7-O-substituted benzoyl substituent that significantly exhibit more potent ACAT2 inhibitory activity and higher ACAT2 isozyme selectivity than 1., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The stereoselective total synthesis of atpenins A4 (2) and B (3), harzianopyridone (4), and NBRI23477 B (5) have been developed using a convergent approach involving the coupling reaction of a common iodopyridine with an aldehyde corresponding to the appropriate side chain of the desired compound. Furthermore, the absolute configurations of atpenin B (3), harzianopyridone (4), and NBRI23477 B (5) have been unambiguously determined.

Most cancer cells have mutations in genes at the G1 checkpoint and repair DNA only in the G2 phase; therefore, the G2 checkpoint is a potential target to develop novel therapy. In the course of screening, a known compound, pycnidione, was isolated from the fungal culture broth of Gloeotinia sp. FKI-3416. Pycnidione irreversibly abrogated bleomycin-induced G2 arrest in Jurkat cells and synergically potentiated the cytotoxicity of bleomycin. To elucidate the mechanism of action, the effect of pycnidione on the signal transduction of the G2 checkpoint was analyzed, showing that the increased phospho-cyclin dependent kinase-1 (CDK1) level caused by bleomycin was abrogated in the presence of pycnidione, indicating that cells did not arrest at the G2 phase. Moreover, under these conditions, Chk1 and Chk2 levels were markedly down-regulated. Thus, we concluded that pycnidione abrogated bleomycin-induced G2 arrest by decreasing Chk1 and Chk2.

Enantioselective total synthesis of atpenin A5, a potent mitochondrial complex II (succinate-ubiquinone oxidoreductase) inhibitor, has been achieved by a convergent approach through a coupling reaction between 5-iodo-2,3,4,6-tetraalkoxypyridine and a side-chain aldehyde. The two key segments were synthesized through ortho-metalation/boronation with (MeO)3B/oxidation with mCPBA, ortho-iodination, halogen dance reaction, Sharpless epoxidation and regioselective epoxide-opening reaction. This synthetic study resulted in the revision of the earlier reported 1H-NMR data of the natural atpenin A5 and the confirmation of the stereochemical assignment.

Selectivity of 96 semisynthetic derivatives prepared from fungal pyripyropene A, originally isolated as a potent inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), toward ACAT1 and ACAT2 isozymes was investigated in the cell-based assay using ACAT1- and ACAT2-expressing CHO cells. Eighteen derivatives including PR-71 (7-O-isocaproyl derivative) showed much more potent ACAT2 inhibition (IC50: 6.0 to 62 nM) than pyripyropene A (IC50: 70 nM). Among them, however, natural pyripyropene A showed the highest selectivity toward ACAT2 with a selectivity index (SI) of >1000, followed by PR-71 (SI, 667).

Several 9-(2-C-cyano-2-deoxy-l-beta-d-arabino-pentofuranosyl)purine derivatives were tested against Kaposi's sarcoma-associated herpesvirus (KSHV)-infected primary effusion lymphoma (PEL) cells. The guanine derivative (3, CNDAG), as well as the 2-amino-6-substituted-purine derivatives 4, 5, and 6, exhibited cell growth inhibitory activity against KSHV-infected cells, but showed no cytotoxicity against KSHV-negative cells at >15 microM concentrations. Therefore, it was found that compounds 3, 4, 5, and 6 showed selective cytotoxicity against PEL cells infected with KSHV.

We investigated the antioxidative effects of fluvastatin (FV or (+/-)-FV), each enantiomer ((+)-FV, (-)-FV) and its major metabolites on lipid peroxidation using rat and human liver microsomes. The extent of NADPH induced microsomal (Ms) lipid peroxidation was determined by thiobarbituric acid (TBA) assay. The antioxidative effect of each compound was shown as the percentage of inhibition on the formation of TBA reactive substance (TBARS) against vehicle control. The antioxidative effects of alpha-tocopherol (Toc), a potent antioxidative vitamin, probucol (PR), a potent antioxidative drug, pravastatin (PV) and simvastatin (SV), HMG-CoA reductase inhibitors, were also tested. The (+/-)-FV inhibit the formation of TBARS by 40 to 70% depending on Ms concentrations. The antioxidative effects of PR and TOC were comparable to those of FV. The inhibitory effects of PV and SV on the formation of TBARS were less potent than (+/-)-FV, PR and TOC. (+)-FV, (-)-FV, and (+/-)-FV inhibited the formation of TBARS by approximately 50% using rat hepatic microsomes. The antioxidative effects of (+)-FV was comparable to that of (-)-FV using human hepatic microsomes. These results indicated that the antioxidative effects of (+)-FV were comparable to those of (-)-FV, although the HMG-CoA reductase inhibitory activity of (+)-FV was 30-fold higher than that of (-)-FV.

A 58-year-old man with a history of cerebral infarction and bleeding due to duodenal ulcer was admitted with fever and arthralgia. Methicillin-sensitive Staphylococcus aureus (MSSA) was isolated from his peripheral blood. Bacteremia with MSSA was diagnosed, and antibiotic therapy was started. However, chest X-ray films and computed tomographic scans disclosed mass shadows in both lungs accompanied by dilated vascular markings. Pulmonary arteriography and magnetic resonance angiography revealed the existence of arteriovenous fistulas in both lungs. Ga scintigraphy disclosed a hot spot in the left lower lobe, consistent with the location of one fistula. This indicated that the fistula might be the focus of MSSA sepsis. Because the patient also had telangiectasia in his gastric mucosa, oral cavity, and nasal cavity, he was given a diagnosis of Rendu-Osler-Weber syndrome.

Aims: To clarify the mechanism for cellular uptake of fluvastatin (FV) into rat primary cultured hepatocytes and human aortic endothelial cells (HAEC)., Methods: Rat primary cultured hepatocytes and Endocell-AO as normal human aortic endothelial cells were used. Effects of incubation time, concentration- and temperature-dependency on cellular FV uptake were investigated after incubation with [14C]-FV and its enantiomers, (+)-FV and (-)-FV. Rat primary cultured hepatocytes were washed with either Na+-containing buffer or Na+-free buffer and incubated with metabolic inhibitors or bile acids. Intracellular radioactivity was measured by liquid scintillation counting. The determination of intracellular unchanged FV and its enantiomers was carried out by stereospecific h.p.l.c., Results: In rat cultured hepatocytes, concentration- and temperature-dependent saturable uptake of [14C]-FV was observed (Km=37.6 microm, V max=869 pmol (mg protein)-1 min-1 ), suggesting a specific uptake mechanism. The uptake of each enantiomer also showed a specific uptake mechanism as observed for the racemate with no difference between enantiomers; (+)-FV, Km=38.5 microm, V max=611 pmol (mg protein)-1 min-1, (-)-FV, Km=41.5 microm, V max=646 pmol (mg protein)-1 min-1. In the presence of cholate and taurocholate, the uptake of FV was inhibited by 39-46%. Pravastatin inhibited FV uptake by 29%. In the absence of Na+, the uptake of FV was markedly inhibited 91-96% by bile acid. The uptake of FV into HAEC at 37 degrees C and 4 degrees C increased with the concentration of FV, but no saturable uptake was observed., Conclusions: FV transport system may be, at least in part, Na+- and ATP-dependent, and may have some features in common with the bile acid transport system and the organic anion transport system. Since saturable uptake was not observed in HAEC, FV appears to be taken up into these cells mainly via nonspecific simple diffusion.

Fluvastatin (FV) is a highly potent inhibitor of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase. Recently, its antioxidant effect caused by inhibiting the formation of low density lipoproteins (LDL) in vitro has been reported. In this study, we reported the antioxidant effects of FV and its major metabolites in human (M-2, M-3, M-4, M-5, and M-7) on lipid peroxidation using rat liver microsomes. The extent of NADPH-induced microsomal (Ms) lipid peroxidation was determined by the thiobarbituric acid (TBA) assay. The antioxidant effect of each compound was shown as the percentage of inhibition on the formation of TBA reactive substances (TBARS) against the vehicle control. Probucol (PR), a potent antioxidant drug, was used as a reference control. The concentration of each compound in this experiment was set at 0.1 mM (final conc.). FV inhibited the formation of TBARS by 30 to 60% without depending on the used Ms concentrations (0.025-0.2 mg protein/ml). The antioxidant effects of M-2, M-3, and M-5 were comparable to that of FV at low Ms concentrations. At the highest Ms concentration, however, the antioxidant effects of these metabolites were considerably higher than that of FV. Inhibition of the formation of TBARS by M-4 or M-7 was approximately 30% of the control and independent of the used Ms concentrations. The antioxidant effect of PR was comparable to those of M-2, M-3, and M-5 in this study. Pravastatin (PV), a potent inhibitor of HMG-CoA reductase, reduced the formation of TBARS around 20% at 0.25 or 0.5 mg protein/ml of Ms concentrations. But the value of percentage of inhibition was around 5% at 0.1 or 0.2 mg protein/ml of Ms concentrations. In conclusion, the antioxidant effects of FV, M-2, M-3, and M-5 were found to be comparable to that of PR.

A case of axillary sweat gland carcinoma which metastasized to both lungs five years after resection of the primary lesion is described. After the resection of right lung metastasis, systemic chemotherapy was performed, but no response was achieved. The patient has no complaints now, but there are new and multiple metastases in both lungs. I propose that the complete remission can be achieved only by resections.