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A series of novel 2,7-disubstituted tetrahydroisoquinoline derivatives were designed and synthesized. Among these derivatives, compounds 1 and 2 exhibited potent inhibitory activity against factor Xa (FXa) and good selectivity with respect to other serine proteases (thrombin, plasmin, and trypsin). In addition, compound 2 exhibited potent anti-FXa activity after intravenous and oral administration to cynomolgus monkeys, showed a dose-dependent antithrombotic effect at 0.1, 0.3, and 1 mg kg(-1) h(-1) in a rat model of venous thrombosis, and significantly reduced the size of brain infarction in a middle cerebral artery occlusion model at a dose of 0.1 mg kg(-1) h(-1). These results suggest that compound 2 (JTV-803) is likely to be useful as both a venous and arterial antithrombotic agent.

A series of benzimidazole derivatives with the side chain on the nitrogen atom oriented to the prime site of factor Xa (FXa) were designed and synthesized. Compounds with substituted aminocarbonylmethyl groups as the side chain showed potent FXa inhibitory activity. Compounds 1 and 2 exhibited most potent inhibitory activity and were effective as anticoagulants in a DIC model.

A variety of novel heterocyclic compounds having thienoazepine, pyrroloazepine, furoazepine, and thienodiazepine skeletons were synthesized, most of which exhibited potent antagonism of [(3)H]-AVP specific binding in assays using rat liver (V1), rat kidney (V2), human platelet plasma membranes, and recombinant human CHO cells (V2), as well as antagonizing AVP-induced hypertension in rats (V1, intravenous) and showing a diuretic effect in rats (V2, oral). By detailed studies of the structure-activity relationships of these compounds, the thienoazepine derivative 1 was found to be a very potent combined V1 and V2 antagonist. After further pharmacological and toxicological evaluation as well as physical properties, the hydrochloride 2 (JTV-605) of compound 1 was selected for clinical studies as a potent AVP antagonist with a long duration of action.

A series of bis(2-(acylamino)phenyl) disulfides, 2-(acylamino)benzenethiols, S-(2-(acylamino)phenyl) alkanethioates, and related compounds were synthesized, and their inhibitory effect on cholesteryl ester transfer protein activity in human plasma was evaluated. This study elucidated the structural requirements for inhibitory activity and determined that the optimum compound was S-(2-((1-(2-ethylbutyl)cyclohexane)carbonylamino)phenyl) 2-methylpropanethioate (27) (JTT-705). This compound achieved 50% inhibition of CETP activity in human plasma at a concentration of 9 microM and 95% inhibition of CETP activity in male Japanese white rabbits at an oral dose of 30 mg/kg. It increased the plasma HDL cholesterol level by 27% and 54%, respectively, when given at oral doses of 30 or 100 mg/kg once a day for 3 days to male Japanese white rabbits.

The aldol reaction of optically active α-alkoxycarbonylamino aldehydes with a silyl enol ether in the presence of a Lewis acid afforded γ-amino-β-hydroxyketones diastereoselectively. The effect of the α-amide proton on the diastereoselectivity is discussed.

During an investigation of drugs for improving the beta-cell response to glucose, we found that 4-cyclohexyl-4-oxobutyric acid selectively improved glucose-stimulated insulin release and glucose tolerance in both normal and diabetic rats. A series of 4-cycloalkyl-4-oxobutyric acids and related compounds were synthesized and evaluated for their effects on the glucose tolerance test and fasting euglycemia. This study elucidated the structural requirements for drug activity and determined that the optimum compound was 4-(trans-4-methylcyclohexyl)-4-oxobutyric acid 7 (JTT-608). This compound improved glucose tolerance from an oral dose of 3 mg/kg and did not change fasting euglycemia even at an oral dose of 30 mg/kg. Selective improvement of glucose-induced insulin secretion was observed in studies using neonatal streptozotocin rats (nSTZ rats) and perfused pancreases isolated from nSTZ rats.

A series of renin inhibitors containing the (2S,3S,5S)-2-amino-1-cyclohexyl-6-methyl-3,5-heptanediol (2-amino-3,5-anti-diol) fragment as a novel transition-state mimic was synthesized, and their biological activities were evaluated. All of the synthesized compounds containing the 2-amino-3,5-anti-diol fragment at the P1-P1' position showed high in vitro renin-inhibitory activity with IC50 values in the 10(-8)-10(-10) M range, and most of them caused a reduction of blood pressure when administered orally to salt-depleted, conscious marmosets. The inhibitor (29) with the 4-hydroxypiperidine residue at the P4 position showed the highest activity in terms of both potency and duration of the blood pressure-lowering effect.

A variety of compounds having a benzopyran such as levcromakalim generally exhibit potent antihypertensive activity. During extensive investigations aimed toward identifying K+ channel openers having selective coronary vasodilation without potent hypotensive and tachycardiac effects, we synthesized a series of 3,4-dihydro-2H-1-benzopyran-3-ol derivatives modified at positions 2, 4, and 6 in the benzopyran ring. Initially, compounds having two methoxymethyl groups at position 2 were found to show a selective effect on coronary blood flow (CoBF) relative to mean arterial pressure (MAP) in anesthetized dogs. To find more potent vasodilators, various benzopyran derivatives modified at position 4 were synthesized and structure-activity relationships were examined by evaluation of the extent and duration of the increase in CoBF in anesthetized dogs. As a result, compounds having a (1,6-dihydro-6-oxopyridazin-3-yl)amino group at position 4, in addition to the two methoxymethyl groups at position 2, were found to be more potent and to have an improved duration of action. Among these compounds, JTV-506, (-)-(3S,4R)-6-cyano-3,4-dihydro-4-[(1,6-dihydro-1-methyl-6-oxopyridaz in-3-yl)amino]-2,2-bis(methoxymethyl)-2H-1-benzopyran-3-ol, exhibited good selectivity for its effect. Administration of this compound (0.03 mg/kg, p.o.) elicited an increase of CoBF without a change of systemic blood pressure and heart rate (HR) in conscious dogs. Further evaluation was performed with respect to (i) the selectivity of its action on the coronary artery versus the aorta and (ii) its effects on MAP, HR, and electrocardiographic ST elevation. As a result, JTV-506 was selected as a potent and selective coronary vasodilator with various pharmacological features favoring clinical development.

A variety of compounds having a benzopyran such as levcromakalim generally exhibit potent antihypertensive activity. During extensive investigations aimed toward identifying K+ channel openers having selective coronary vasodilation without potent hypotensive and tachycardiac effects, we synthesized a series of 3,4-dihydro-2H-1-benzopyran-3-ol derivatives modified at positions 2, 4, and 6 in the benzopyran ring. Initially, compounds having two methoxymethyl groups at position 2 were found to show a selective effect on coronary blood flow (CoBF) relative to mean arterial pressure (MAP) in anesthetized dogs. To find more potent vasodilators, various benzopyran derivatives modified at position 4 were synthesized and structure-activity relationships were examined by evaluation of the extent and duration of the increase in CoBF in anesthetized dogs. As a result, compounds having a (1,6-dihydro-6-oxopyridazin-3-yl)amino group at position 4, in addition to the two methoxymethyl groups at position 2, were found to be more potent and to have an improved duration of action. Among these compounds, JTV-506, (-)-(3S,4R)-6-cyano-3,4-dihydro-4-[(1,6-dihydro-1-methyl-6-oxopyridaz in-3-yl)amino]-2,2-bis(methoxymethyl)-2H-1-benzopyran-3-ol, exhibited good selectivity for its effect. Administration of this compound (0.03 mg/kg, p.o.) elicited an increase of CoBF without a change of systemic blood pressure and heart rate (HR) in conscious dogs. Further evaluation was performed with respect to (i) the selectivity of its action on the coronary artery versus the aorta and (ii) its effects on MAP, HR, and electrocardiographic ST elevation. As a result, JTV-506 was selected as a potent and selective coronary vasodilator with various pharmacological features favoring clinical development.

A series of low molecular renin inhibitors (molecular weight ∗< 600) were prepared and their biological activities were evaluated. The inhibitors containing indole-2-carbonyl moieties at the P3 position and 2-amino-3,5-anti-diol fragment at the P1-P1′ position showed renin inhibitory activities with IC50 of 10−8 M order and good blood pressure lowering effects after oral administration to sodium-depleted marmosets.

During an investigation of drugs for improving the β-cell response to glucose, we found that 4-cyclohexyl-4-oxobutyric acid selectively improved glucose-stimulated insulin release and glucose tolerance in both normal and diabetic rats. A series of 4-cycloalkyl-4-oxobutyric acids and related compounds were synthesized and evaluated for their effects on the glucose tolerance test and fasting euglycemia. This study elucidated the structural requirements for drug activity and determined that the optimum compound was 4-(trans-4-methylcyclohexyl)-4-oxobutyric acid 7 (JTT-608). This compound improved glucose tolerance from an oral dose of 3 mg/kg and did not change fasting euglycemia even at an oral dose of 30 mg/kg. Selective improvement of glucose-induced insulin secretion was observed in studies using neonatal streptozotocin rats (nSTZ rats) and perfused pancreases isolated from nSTZ rats.

The structures of WS1358A1 and B1, new dehydropeptidase inhibitors isolated from Streptomyces parvulus subsp. tochigiensis No. 1358, have been established to be 2-hydroxy-2-hydroxyaminocarbonyl-3-methylglutaric acid (1) and 2-hydroxy-2-hydroxyaminocarbonylglutaric acid (2), respectively, on the basis of spectroscopic evidence and synthesis of the racemates.

The structures of compounds 3 (and 4) and 5 (and 6) derived from the natural products WS1358A1 (1) (and B1 (2)) have been determined by their spectroscopic evidence. By taking advantage of these transformations, an improved synthesis of A1 (1, racemate) has been achieved.

A series of novel 2,7-disubstituted tetrahydroisoquinoline derivatives were designed and synthesized. Among these derivatives, compounds 1 and 2 (JTV-803) exhibited potent inhibitory activity against FXa and good selectivity with respect to other serine proteases (thrombin, plasmin, and trypsin). In addition, compound 2 exhibited potent anti-FXa activity after intravenous and oral administration to cynomolgus monkey, and showed a dose-dependent antithrombotic effect in a rat model of venous thrombosis.

Small-molecule nociceptin antagonists were synthesized to examine their therapeutic potential. After a 4-aminoquinoline derivative was found to bind with the human ORL1 receptor, a series of 4-aminoquinolines and related compounds were synthesized and their binding was evaluated. Elucidation of structure−activity relationships eventually led to the optimum compounds. One of these compounds, N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide hydrochloride (11) not only antagonized nociceptin-induced allodynia in mice but also showed analgesic effect in a hot plate test using mice and in a formalin test using rats. Its analgesic effect was not antagonized by the opioid antagonist naloxone. These results indicate that this nociceptin antagonist has the potential to become a novel type of analgesic that differs from μ-opioid agonists.

Small-molecule nociceptin antagonists were synthesized to examine their therapeutic potential. After a 4-aminoquinoline derivative was found to bind with the human ORL(1) receptor, a series of 4-aminoquinolines and related compounds were synthesized and their binding was evaluated. Elucidation of structure-activity relationships eventually led to the optimum compounds. One of these compounds, N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide hydrochloride (11) not only antagonized nociceptin-induced allodynia in mice but also showed analgesic effect in a hot plate test using mice and in a formalin test using rats. Its analgesic effect was not antagonized by the opioid antagonist naloxone. These results indicate that this nociceptin antagonist has the potential to become a novel type of analgesic that differs from mu-opioid agonists.

Isoxazolidine-3,5-dione 2 (JTT-501), one of the cyclic malonic acid derivatives, was found to decrease blood glucose at an oral dose of 38 mg/kg/day in KKAy mice and is currently undergoing evaluation in phase II clinical trials. Further studies on a series of malonic acids and related compounds showed that the 1,3-dicarbonyl structure was important for insulin-sensitizing activity. Dimethyl malonate 10, which was selected as a successor for 2, was the optimum compound in a series of 1,3-dicarbonyl compounds and was more potent than the corresponding thiazolidine-2,4-dione 1.

The structure of a novel immunomodulator, nectrisine (1), has been elucidated on the basis of chemical and spectroscopic evidence. Its absolute stereochemistry was predicted on the basis of the dibenzoate chirality rule and finally confirmed by a synthesis from D-glucose.

WS-7528, produced by Streptomyces sp. No. 7528, was extracted from cultured broth, purified by solvent extraction followed by chromatography on silica gel and then isolated as pale yellow powder (C16H14O5, mp 95-98 degrees C). WS-7528 inhibited estrogen binding to its receptor protein in rat uterine cytosol. The IC50 value of WS-7528 for partially purified rat uterine cytosol receptor was 5.7 x 10(-8) M. This compound was found to induce the growth of the estrogen dependent cell line MCF-7. WS-7528 was tested orally and subcutaneously in immature rats to confirm its effect on the growth of the uterus. WS-7528 has also weak anti-inflammatory activity on the carrageenin paw edema of the rat model.

The structure elucidation and total synthesis of chryscandin (1), a new antifungal antibiotic produced by Chrysosporium pannorum No.4629, is reported.

The structure of amauromine, a novel alkaloid with potent vasodilating activity was determined chemically and spectroscopically to be (5aS, 7aS, 8aR, 13aS, 15aS, 16aR)-8a, 16a-bis-(1,l-dimethyl-2-propenyl)-5a, 8,8a,13,13a,15a,16,16a-octahydropyrazino [1',2':1, 5;4', 5':1',5']dipyrrolo[2,3-b:2',3'-b']- diindole-7, 15(5H,7aH)-dione.

A new antitumor antibiotic, WF-3405 was isolated from the culture of Amauroascus aureus F-3405. The structure has been determined as 1, 5-dioxiranyl-1, 2, 3, 4, 5-pentanepentanol on the basis of spectroscopic and chemical evidence. WF-3405 exhibits strong inhibitory activity against various murine tumors including leukemia P388, leukemia L1210 and Lewis lung carcinoma.

The Jones oxidation of shikoccin (1), the major diterpenoid of Rabdosia shikokiana var. occidentalis, unexpectedly provided products 3 and 4. Tetrahydroshikoccin (6) afforded the abietane-type compound 11 upon Jones oxidation.

The structures of biphenomycins A and B, novel peptide antibiotics produced by a strain of Streptomyces, have been established as 1 and 2, respectively, on the basis of spectroscopic and chemical evidence. They are unique in that they are cyclic peptides containing a biphenyl moiety included in a 15-membered ring and show potent antibacterial activities especially against Gram-positive bacteria.

WB-3559 A, B, C and D were produced by a bacterium which was classified as a member of the genus Flavobacterium. These compounds were purified by solvent extraction followed by chromatography on silica gel and then isolated by HPLC. The chemical structures were determined on the basis of chemical and spectroscopic evidence as in the succeeding papers. WB-3559 A, B, C and D stimulated rabbit plasma euglobulin clot lysis time. A chemically synthesized compound (WB-3559 D-syn) stimulated mouse plasma euglobulin clot lysis time when injected intravenously.

Total synthesis of amauromine ( 1 ), a novel alkaloid possessing two reversed prenyl groups in its molecule, was described.

A complex of the new antitumor antibiotics (WF-1360, WF-1360A, B, C, D, E and F) was produced by Rhizopus sp. No. F-1360. Structural studies of these compounds suggested that they were novel 16-membered-ring lactones having an oxazole ring in their structures. WF-1360 was found to be identical with rhizoxin (1) and WF-1360B, C, E and F were de-termined to be homologues of 1 with structures 2, 3, 4 and 5, respectively. These compounds were cytotoxic when tested on P388 leukemia cells in vitro. WF-1360 was highly active against leukemia L1210 and melanoma B16. They also exhibited potent antifungal activities, but weak antimicrobial activities against some Gram-positive or negative bacteria.

The structures of WB-3559 A, B, C and D, new fibrinolytic agents isolated from Flavobacterium sp. No. 3559, have been elucidated to be as shown in 1, 2, 3 and 4, respectively, on the basis of chemical and spectroscopic evidence. Total synthesis of WB-3559 D (4) was achieved starting from the optically active aldehyde 14.

Vinigrol, produced by a fungal strain identified as Virgaria nigra, was extracted from the cultured mycelium, purified by solvent extraction followed by chromatography on silica gel and then isolated as crystals (C20H34O3, mp 108 degrees C). Vinigrol decreased arterial blood pressure of anesthetized normotensive rats dose-dependently when administered intravenously. Vinigrol inhibited platelet activating factor and epinephrine induced platelet aggregation.

The structure of WF 3681 ( 1 ), an aldose reductase inhibitor isolated from a Chaetomella species, has been determined on the basis of its physical and chemical properties and confirmed by a total synthesis.

On the basis of chemical and spectroscopic evidence, the antibiotic lavendomycin (C29H50N10O8) has been shown to be a hexapeptide 1 containing a new amino acid, 3-methylarginine, in the molecule.

The structure of the immunomodulator FR 900483 (C5H9NO3) has been shown to be 1 on the basis of chemical and spectroscopic evidence and confirmed by a synthesis from D-glucose.

Six cardiac glycosides having an unusual sugar linkage, elaeodendrosides B, C, F, G, K and L, were isolated from seeds of Elaeodendron glaucum . These were characterized on the basis of the physical data and the results obtained by improved procedures for cleavage of their glycoside linkage.

The structure of FR900490 (C14H22N6O6) has been shown to be 1 on the basis of its physical and chemical properties and confirmed by a synthesis.

The new antitumor antibiotics, FR-900405 and FR-900406, were isolated from the culture broth of Actinomadura pulveracea sp. nov. No. 6049. These compounds which contain sulfur in the molecule, represent a novel class of antitumor agents. FR-900405 and FR-900406 are highly active in mice against experimental tumors and exhibit antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi.

WB-3559 A, B, C, and D are new fibrinolytic agents isolated from Flavobacterium sp. No. 3559. The structure of these four compounds and the total synthesis of WB-3559 D are described.

Structure of amauromine (1a), a novel alkaloid with potent vasodilating activity has been established by chemical and spectroscopic evidences.

A platelet activating factor (PAF) antagonist, designated as FR-49175, was isolated from fermentation products of Penicillium terlikowskii and identified as bisdethiobis(methylthio)-gliotoxin (1). The IC50 value of this compound for PAF-induced rabbit platelet aggregation was 8.4 μM.Some derivatives of bisdethiobis(methylthio)gliotoxin (1) were synthesized and their inhibitory activities of PAF-induced platelet aggregation were examined. Among these compounds, 5a, 6-anhydrobisdethio-3, 10a-bis(methylthio)gliotoxin (8) showed the most potent PAF inhibitory activity (IC50; 4.4 μM).

WF-10129 is an angiotensin converting enzyme (ACE) inhibitor produced by Doratomyces putredinis. IC50 of the compound is 1.4 X 10(-8) M for the ACE activity. WF-10129 was purified from cultured filtrate by successive ion exchange chromatography and HPLC. The chemical structure 1 was elucidated on the basis of spectroscopic and chemical evidence. The compound is a dipeptide composed of L-tyrosine and a novel amino acid. WF-10129 inhibits the pressor response of angiotensin I when administered intravenously at 0.3 mg/kg in rats.