Facile conversion of 23-hydroxyspirosolane into pregnane

Two novel reactions with regard to steroidal alkaloid sapogenols obtained from ripe tomato have been found. These reactions have been attained by simple facile method in only refluxing with pyridine and water. One is isomerization of a spirosolane derivative, isoesculeogenin A (2), into a rare solanocapsine derivative, esculeogenin B (3), disclosing a chemical correlation between isoesculeogenin A and esculeogenin B. Another is conversion of a 23-hydroxyspirosolane derivative, esculeogenin A (1), into a pregnane derivative (4), presenting an epoch-making method for derivation of steroidal hormone material.     

The preparation of ferrocenedithiocarboxylic acid derivatives and their spectral properties

Ferrocenedithiocarboxylic acid and various derivatives have been prepared and characterized. The molecular extinction coefficients for the n → π transition of the thiocarbonyl group in the visible spectra of these derivatives are 10–15 fold greater than expected for aromatic dithio acids.     

Tomato steroidal alkaloid glycosides, esculeosides A and B, from ripe fruits

Major novel steroidal alkaloid glycosides, named esculeoside A (1) and esculeoside B (2), have been isolated from the pink color-type and the red color-type, respectively, of the ripe tomato fruits of Lycopersicon esculentum MILL. for the first time. The structures of 1 and 2 have been characterized as 3-O-β-lycotetraosyl (5S,22S,23S,25S)-23-acetoxy-3β,27-dihydroxyspirosolane 27-O-β-d-glucopyranoside and 3-O-β-lycotetraosyl (5S,22S,23R,25S)-22,26-epimino-16β,23-epoxy-3β,23,27-trihydroxycholestane 27-O-β-d-glucopyranoside, respectively.     

Discovery of an orally-active nonsteroidal androgen receptor pure antagonist and the structure-activity relationships of its derivatives

The 3-(4-cyano-3-trifluoromethylphenyl)-5,5-dimethylthiohydantoin derivatives which have carboxy-terminal side chains were synthesized and their agonistic/antagonistic activities against androgen receptor (AR) measured. Among them, compound 13b showed antagonistic activity (IC50=130 nM) with no agonistic activity even at 10000 nM. This compound exhibited significant metabolic stability and oral antiandrogenic activity (ED50=7 mg/kg).     

Conversion of esculeoside A into esculeogenin B

Conversion of the spirosolane-type glycoside, esculeoside A, a major component contained in the ripe tomato Lycopersicon esculentum fruits, into a solanocapsine-type sapogenol, esculeogenin B-2, (5alpha,22S,23R,25S)-22,26-epimino-16beta,23-epoxy-3beta,23,27-trihydroxycholestane, and esculeogenin B-1, (5alpha,22R,23S,25S)-22,26-epimino-16beta,23-epoxy-3beta,23,27-trihydroxycholestane, which are rare naturally occurring compounds was attained by acid hydrolysis with 2 N HCl in dioxane and water (1 : 1).     

Synthesis and chemiluminescent activity of 8,9‐dihydrobenzo[g] pyridazino[4,5‐b]indole‐7,10(11H)‐diones

Substituted and unsubstituted naphthylamines were transformed into the corresponding triazole derivatives, which were converted to dimethyl 1H‐benz[g]indole‐2,3‐dicarboxylates by photocyclization. The reaction of the diesters with hydrazine hydrate gave the corresponding 8,9‐dihydrobenzo[g]‐pyridazino[4,5‐b]indole‐7,10(11H)‐diones (5) . One of compounds 5 was found to have chemiluminescent activity similar to luminol.     

Three New Resin Glycosides and a New Tetrahydropyran Derivative from the Seeds of <i>Quamoclit pennata</i>

Three new resin glycosides, quamoclins V (1), VI (2), and VII (3) and a new tetrahydropyran derivative, quamopyran (4), were isolated from the seeds of Quamoclit pennata BOJER (Convolvulaceae). The chemical structures of these compounds were determined primarily on the basis of spectroscopic data. The carboxyl group of the aglycone, 11S-convolvulinolic acid, of 1 and 2 was linked intermoleculary with a hydroxy group of the sugar moiety to form a macrocyclic ester structure, as in already known jalapins, and 3 was an acylated glycosidic acid methyl ester. All of the sugar moieties of 1-3 were acylated by one 2S-methylbutyric acid. Compound 4 was a diketone having a tetrahydropyran ring.     

Garlicnins B(1), C(1), and D, from the fraction regulating macrophage activation of Allium sativum

Several novel sulfides from acetone extracts of bulbs of garlic (Allium sativum L.), were identified and investigated. These were named garlicnins B(1) (1), C(1) (2), and D (3), and they were found to have the ability to control macrophage activation. Garlicnins B(1) (1) and C(1) (2) possess a new skeleton of cyclic sulfoxide and their structures of garlicnins B(1) (1) and C(1) (2) were characterized as 3,4-dimethyltetrahydrothiophene-S-oxide derivatives carrying the substitutions of a propenyl and a sulfenic acid, and an allyldithiine and a 1-propene-sulfenic acid (a), respectively. The mechanism of the proposed production of these compounds is discussed. Garlicnin D (3), dithiine-type, was estimated to be derived by addition of (a)+allyl thiosulfenic acid (b) derived from allicin. The identification of these novel sufoxides from onion and garlic accumulates a great deal of new chemistry to the Allium sulfide field, and future pharmacological investigations aid the development of natural, healthy foods and anti-cancer agents that could potentially prevent or combat disease.     

HPLC retention behaviors of poly-aromatic-hydrocarbones on Cu(II)-octabromotetrakis(4-carboxyphenyl)porphine derivatives-immobilized aminopropyl silica gels in polar and non-polar eluents

As one of approaches of developing novel HPLC stationary phases, we prepared Cu-octabromotetrakis(4-carboxyphenyl)porphine derivative-immobilized silica gels (Cu-OBTCPP(D)), and evaluated the availability of the resultant Cu-OBTCPP(D) as a stationary phase for separation of poly-aromatic-hydrocarbons (PAHs) and their related compounds. A Cu-OBTCPP(D) column was revealed to have an ability to separate simple PAHs and be useful as a stationary phase in both polar and non-polar eluents. The retention property of the Cu-OBTCPP(D) column was evaluated in various comparative experiments using commercially available columns. In comparison with 2-(1-pyrenyl)ethyl dimetylsilyl silica gel column (PYE column) regarding the retention behavior for PAHs etc., the Cu-OBTCPP(D) column showed stronger interactions involving pi electron in non-polar eluent than PYE column. In comparison with a pentabromobenzyloxy propylsilyl silica gel column (PBB column) regarding the influence of bromination, the Cu-OBTCPP(D) column was affected differently from the PBB column. In comparison with nitrophenylethyl silica gel column (NPE column) regarding the retention behavior for compounds having a dipole in a non-polar eluent, the Cu-OBTCPP(D) column showed electrostatic interactions such as dipole-dipole interaction equivalent to or larger than the NPE column.     

New iridoid glucosides from the aerial parts of Verbena brasiliensis

Two new iridoid glucosides, verbenabraside A (1) and verbenabraside B (2), were isolated from the aerial parts of Verbena brasiliensis VELL., along with six known iridoid glucosides, gelsemiol 3-O-beta-D-glucoside (3), verbraside (4), 9-hydroxysemperoside (5), griselinoside (6), aralidioside (7), and 6alpha-hydroxyforsythide dimethyl ester (8), three known phenylethanoid glycosides, 2-phenylethyl O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (9), acteoside (10), and leucosceptoside A (11), two known lignan glucosides, dihydroxymethyl-bis(3,5-dimethoxy-4-hydroxyphenyl) tetrahydrofuran-9 (or 9')-O-beta-glucopyranoside (12) and (+)-lyoniresinol 3alpha-O-beta-D-glucopyranoside (13), a known methyl salicylate glucoside, methyl 2-O-beta-D-glucopyranosylbenzoate (14), and two known sterols, beta-sitosterol 3-O-beta-D-glucopyranoside (15) and beta-sitosterol (16). Their chemical structures were determined on the basis of spectroscopic data. Compound 1 exhibited stronger scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl than that of alpha-tocopherol.