A New Glycosidic Acid, Muricatic Acid D, and Resin Glycosides, Muricatins X and XI, from the Crude Resin Glycoside Fraction of the Seeds of Ipomoea muricata.

Alkaline hydrolysis of crude resin glycoside fraction of the seeds of Ipomoea muricata (L.) Jacq. (Convolvulaceae) yielded a new glycosidic acid, muricatic acid D; three known glycosidic acids, namely, muricatic acids A, B, and C; and three known organic acids, namely, isobutyric, 2S-methylbutyric, and 2S-methyl-3S-hydroxybutyric acid. Two new genuine resin glycosides with macrolactone structures (jalapins), muricatins X and XI, were also isolated from the fraction. Their structures were determined using spectroscopic data and chemical evidence.

Screening of Promising Chemotherapeutic Candidates from Plants against Human Adult T-Cell Leukemia/Lymphoma (VII): Active Principles from Thuja occidentalis L.

During the screening of novel chemotherapeutic candidates from plants against adult T-cell leukemia/lymphoma, we identified that the extracts of Thuja occidentalis (Cupressaceae) showed potent anti-proliferative activity in MT-1 and MT-2 cells. Therefore, we attempted to isolate the active components from this plant. We isolated and identified 32 compounds (1-32; eight lignans, 18 terpenoids, and six flavonoids) from the extracts of the leaves and cones. Their structures were determined by spectroscopic analysis. Several of the isolated compounds inhibited the growth of both cell lines. Lignans showed more potent activity than other classes of compounds. A comparison of the activities of compounds 1-8 revealed that the presence of a trans-lactone (linkage of C-6 to C-7) correlated with increased activity. Diterpenes showed moderate activity, and the presence of a ketone moiety at the C-7 position correlated with increased activity in compounds 12-21. In addition, biflavones showed moderate activity, and the presence of methoxy functions appeared to influence the activity of these compounds. Several lignans were lead compound of anti-cancer reagent (etoposide). In conclusion, not only lignans, but also diterpenes and/or biflavones, may be promising candidates for the treatment of adult T-cell leukemia/lymphoma.

Screening of Promising Chemotherapeutic Candidates from Plants against Human Adult T-Cell Leukemia/Lymphoma (VI): Cardenolides from Asclepias curassavica.

In the course of our screening program for novel chemotherapeutic candidates from plants against adult T-cell leukemia/lymphoma, the extracts of Asclepias curassavica L. showed potent activity against MT-1 and MT-2 cells. Therefore, we attempted to isolate their active components. We identified a new cardenolide, 19-dihydrocalactinic acid methyl ester (1), along with 16 known cardenolides (2-17). Their structures were determined on the basis of spectroscopic data. Almost all of the isolated cardenolides inhibited the growth of both tumor cell lines. All the doubly linked cardenolides (11-17) except for 14 showed more potent activity than the other cardenolides. A comparison of the activities of 11, 14 and 16 revealed that the presence of hydroxy or acetoxy functional groups at C-16 led to a decrease in the activity. The 50% effective concentration (EC50) value of calotropin (11) against MT-2 cells was comparable to the potency of the clinical antineoplastic drug doxorubicin. The cytotoxic effect of 11 toward normal mononuclear cells obtained from the peripheral blood (PB-MNCs) was observed at a concentration 6 to 12 times higher than that used to induce growth inhibition against MT-1 and MT-2 cells. The proportions of annexin V-positive cells after 72 h of treatment with 11 were increased, indicating that it significantly induced apoptosis in MT-1 and MT-2 cells in a concentration-dependent manner. Cell cycle experiments demonstrated that 11 arrested MT-1 and MT-2 cells at the G2/M phase. Therefore, compound 11 may be a promising candidate for the treatment of adult T-cell leukemia/lymphoma.

Two New Triterpene Glycosides in the Roots of Uraria crinita.

Two new triterpene glycosides, 24-deoxyoxytrogenin 3-O-α-L-rhamnopyranosyl (1→2)[ß-D-glucopyranosyl]-ß-D-galactopyranosyl (1→2)-ß-D-glucuronopyranoside and sophoradiol 3-O-α-L-rhamnopyranosyl (1→2)-ß-D-glucuronopyranosyl (1→2)-ß-D-glucuronopyranoside with four known glycosides were isolated from a Chinese natural medicine, the roots of Uraria crinita (L.) DESV. Their structures were determined by chemical and spectral methods.

Antitumor Allium Sulfides.

We examined the sulfides in onion (Allium cepa L.), Welsh onion (A. fistulosum L.), and garlic (A. sativum L.), and obtained three new thiolane-type sulfides (onionins A1-A3) from onion; two new thiabicyclic-type sulfides (welsonins A1, A2), together with onionins A1-A3, from Welsh onion; and six new acyclic-type sulfides (garlicnins L-1-L-4, E, and F), ten new thiolane-type sulfides (garlicnins A, B1-B4, C1-C3, K1, and K2), and three new atypical cyclic-type sulfides (garlicnins G, I, and J) from garlic. Acetone extracts showed the potential of these sulfides in inhibiting the polarization of M2 activated macrophages that are capable of suppressing tumor-cell proliferation. The effect of the thiolane-type sulfide of a major component, onionin A1, on tumor progression and metastasis in both osteosarcoma and ovarian cancer-bearing mouse models was then examined. Tumor proliferation was depressed, and tumor metastasis was controlled by regulating macrophage activation. These results showed that onionin A1 is an effective agent for controlling tumors in both in vitro and in vivo models, and that the antitumor effects observed in vivo are likely caused by reversing the antitumor immune system. Activation of the antitumor immune system by onionin A1 might be an effective adjuvant therapy for patients with osteosarcoma, ovarian cancer and other malignant tumors. Based on these findings, pharmacological investigations will be conducted in the future to develop natural and healthy foods and anti-cancer agents that can prevent or combat disease.

Atypical Cyclic Sulfides, Garlicnins G, I, and J, Extracted from Allium sativum.

Newly characterized, atypical sulfides, garlicnins G (1), I (2), and J (3), were isolated from the acetone extracts of garlic bulbs, Allium sativum. Their production pathways are regarded as different from those of cyclic sulfoxides, 3,4-dimethyltetrahydrothiophene-S-oxide derivatives such as onionins A1-A3, garlicnins B1-B4 and C1-C3.

Acylated Glycosidic Acid Methyl Esters Generated from the Convolvulin Fraction of Rhizoma Jalapae Braziliensis by Treatment with Indium(III) Chloride in Methanol.

Four hexaglycosides of methyl 3S,12S-dihydroxyhexadecanoate (1-4) were provided after treatment of the crude convolvulin fraction from Rhizoma Jalapae Braziliensis (the root of Ipomoea operculata (GOMES) MART., Convolvulaceae) with indium(III) chloride in methanol. The structures of 1-4 were elucidated on the basis of spectroscopic and chemical methods. Their sugar moieties were partially acylated with organic acids including (3S,9R)-3,6:6,9-diepoxydecanoic (exogonic) acid, (E)-2-methylbut-2-enoic (tiglic) acid, and isovaleric acid.

A New Resin Glycoside, Muricatin IX, from the Seeds of Ipomoea muricata.

A new resin glycoside, named muricatin IX (1), was isolated from the seeds of Ipomoea muricata (L.) JACQ. (Convolvulaceae). The structure of 1 was determined on the basis of spectroscopic data as well as chemical evidence. Compound 1 is the first representative of resin glycosides in which an organic acid connects the sugar moiety and the aglycone moiety to form macrocyclic ester ring.

Antiviral Activity of Four New Resin Glycosides Calysolins XIV-XVII from Calystegia soldanella against Herpes Simplex Virus.

Four new resin glycosides, named calysolins XIV (1), XV (2), XVI (3), and XVII (4) were isolated from the leaves, stems, and roots of Calystegia soldanella ROEM.. et SCHULT. (Convolvulaceae). Their structures were determined based on spectroscopic and chemical evidence, and consisted of two different types: those (1) with a macrolactone structure and those (2-4) with a non-macrolactone structure. Their sugar moieties were partially acylated by specific organic acids, including tiglic, 2S-methylbutyric, and 2S,3S-nilic acids. Additionally, evaluation of the antiviral activity of 1-4 revealed effects against the herpes simplex virus type 1.

Five new resin glycoside derivatives isolated from the convolvulin fraction of seeds of Quamoclit pennata after treatment with indium(III) chloride in methanol.

Three new acylated methyl glycosides and two new acylated glycosidic acid methyl esters were isolated after treatment of the crude ether-insoluble resin glycoside (convolvulin) fraction from seeds of Quamoclit pennata BOJER (Convolvulaceae) with indium(III) chloride in methanol. Their structures were elucidated on the basis of spectroscopic data and chemical conversions.

Four new acylated glycosidic acid methyl esters isolated from the convolvulin fraction of seeds of Quamoclit pennata after treatment with indium(III) chloride in methanol.

Four new acylated glycosidic acid methyl esters were isolated after treatment of the crude ether-insoluble resin glycoside (convolvulin) fraction obtained from the seeds of Quamoclit pennata BOJER (Convolvulaceae) with indium(III) chloride in methanol. Their structures were elucidated on the basis of spectroscopic data and chemical conversions.

Calysolins X-XIII, resin glycosides from Calystegia soldanella, and their antiviral activity toward herpes simplex virus.

Four new resin glycosides having macrolactone structures (jalapins), named calysolins X (1)-XIII (4), were isolated from the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae). Their structures were determined on the basis of spectroscopic data as well as chemical evidence. The sugar moieties of 1-4 were partially acylated by some organic acids, including tiglic acid, 2S-methylbutyric acid, and 2S,3S-nilic acid. Additionally, the antiviral activity of 1-4 toward herpes simplex virus type 1 was evaluated. All the compounds showed antiviral activity.

Calysolins V-IX, resin glycosides from Calystegia soldanella and their antiviral activity toward herpes.

Five new resin glycosides having macrolactone structures (jalapins), named calysolins V-IX (1-5), were isolated from the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae). Their structures were determined on the basis of spectroscopic data as well as chemical evidence. The isolated compounds could be classified into two macrolactone types-one having a 22-membered ring (1-4) and the other with a 27-membered ring (5). The sugar moieties of 1-5 were found to exist in partially acylated forms comprising 2S-methylbutyric acid and tiglic acid. Compounds 4 and 5 are the first representatives of the calysolic acid C as the component glycosidic acid. Additionally, the antiviral activity of 1-5, together with calysolins I-IV and soldanelline B, which are previously isolated jalapins from this plant, toward herpes simplex virus type 1 was evaluated. All the compounds showed antiviral activity.

Acyclic sulfides, garlicnins L-1-L-4, E, and F, from Allium sativum.

Six novel acyclic sulfides, named garlicnins L-1-L-4 (1-4), E (5), and F (6), were isolated from the acetone extracts, with the ability to suppress M2 macrophage activation, of the bulbs of garlic (Allium sativum L.), and their chemical structures were characterized.

Conversion of tomato saponins to pregnane derivatives.

Here reports new conversions methods of tomato saponins, esculeoside A (1) and a mixture of esculeosides B-1 (2) and B-2 (3), (the latter two were obtained from tomato cans) into pregnane derivative (5) by an alkal treatment followed by acid treatment. Compound 1 or a mixture of 2 and 3 were each refluxed with 1 N KOH to afford a characteristic pyridine steroidal glycoside (4), which was then treated with 2 N HCl-MeOH to afford a pregnane derivative, 3ß-hydroxy-5α-pregn-16-en-20-one (5). The results of the above two reactions indicated that tomato saponins are chemically closely related to pregnane hormones. We assume that the assimilated tomato saponins via the small intestine are metabolized into pregnane derivatives, demonstrating various bioactivities such as anti-cancer, anti-osteoporosis, and anti-menopausal disorder activities.

Isolation and structural characterization of eight new resin glycosides, calyhedins XVI-XXIII, from the rhizomes of Calystegia hederacea.

Biological effects attributed to resin glycosides, including cytotoxicity against cancer cells and antibacterial, multidrug resistance-modulating, and antiviral activities have been documented. Penta-glycosides composed of calysolic acid A or calyhedic acid A, which are glycosidic acid components of the crude resin glycoside fraction of Calystegia hederacea, have not yet been isolated from this plant. In this study, eight new resin glycosides, termed calyhedins XVI (1)-XXIII (8), were isolated from the rhizomes of C. hederacea. Compounds 1-8 are penta- or hexa-glycosides with macrolactone structures, and their sugar moieties are partially acylated by five organic acids, including 2S-methylbutyric, (E)-2-methylbut-2-enoic, and 2R-methyl-3R-hydroxybutyric acids. Compounds 1-5 are the first identified macrocyclic resin glycosides with five monosaccharides obtained from this plant, and 2 and 4 are the first to be characterized as containing calyhedic acid A as the glycosidic acid component. Compounds 1-8 were of the four following macrolactone types: one with a 22-membered ring (5), another with a 23-membered ring (6-8), the third with a 27-membered ring (1, 3), and the fourth with a 28-membered ring (2, 4). Compounds 2-8 exhibited cytotoxic activity against HL-60 human promyelocytic leukemia cells comparable to that of the positive control, cisplatin.

Identification and characterization of organic and glycosidic acids in the crude resin glycoside fraction of Ipomoea lacunosa seeds.

Resin glycosides are commonly found in plants belonging to the Convolvulaceae family. Ipomoea lacunosa L. (Convolvulaceae) is an herbaceous vine native to the United States. The resin glycosides of this plant have not been studied in detail. In this study, the components of the crude resin glycoside fraction extracted from the seeds of I. lacunosa are characterized. Alkaline hydrolysis of the crude resin glycoside fraction obtained from methanolic extract of the seeds yielded three organic acids, namely, 2S-methylbutyric, (E)-2-methylbut-2-enoic, and 2R-methyl-3R-hydroxybutyric acids, and a glycosidic acid fraction. Acidic hydrolysis of the glycosidic acid fraction yielded hydroxyl fatty acid components, including 7S-hydroxydecanoic, 11S-hydroxytetradecanoic, 11S-hydroxyhexadecanoic, 3S,11S-dihydroxytetradecanoic, 3S,11S-dihydroxyhexadecanoic, and 3S,12S-dihydroxyhexadecanoic acids, as well as monosaccharide components, including d-glucose, d-quinovose, d-fucose, and l-rhamnose. Trimethylsilyldiazomethane-hexane treatment of the glycosidic acid fraction further yielded eleven previously undescribed glycosidic acid methyl esters and two known glycosidic acid methyl esters. The structures of the obtained compounds were characterized using various spectral techniques. Four of the undescribed compounds were hexaglycosides, five were heptaglycosides, and two were octaglycosides. The aglycone of these compounds was either methyl 11S-hydroxytetradecanoate, methyl 3S,11S-dihydroxytetradecanoate, or methyl 3S,11S-dihydroxyhexadecanoate. Among the undescribed compounds identified, eight contained novel glycans, and three were rare bisdesmosides with sugar linkages at the C-3 and C-11 positions of methyl 3S,11S-dihydroxytetradecanoate.

Identification and characterization of organic and glycosidic acids in the crude resin glycoside fraction of Ipomoea alba seeds.

Resin glycosides act as laxatives in crude drugs derived from plants of the Convolvulaceae family. These compounds have exhibited antibacterial, ionophoric, anti-inflammatory, antiviral, and multidrug resistance-modulating properties, as well as cytotoxicity against cancer cells. This study investigated the organic acid, hydroxyl fatty acid, monosaccharide, and glycosidic acid components of the crude resin glycoside fraction obtained from the methanol extract of Ipomoea alba L. (Convolvulaceae) seeds, which was subjected to alkaline and acidic hydrolysis. The alkaline hydrolysis yielded acetic, isobutyric, (E)-2-methylbut-2-enoic, and 2S-methyl-3S-hydroxybutyric acids as organic acid components, along with a glycosidic acid fraction. The acidic hydrolysis of the glycosidic acid fraction resulted in the isolation of 11S-hydroxytetradecanoic and 11S-hydroxyhexadecanoic acids as hydroxyl fatty acid components, as well as d-glucose, d-quinovose, d-fucose, d-xylose, and l-rhamnose as monosaccharide components. In addition, 10 new glycosidic acid methyl esters were isolated from the glycosidic acid fraction treated with trimethylsilyldiazomethane-hexane, along with one known glycosidic acid methyl ester. Of these, eight compounds contained new glycans. Four of these compounds were unusual natural glycosides with four glycosidic linkages to one monosaccharide. Their structures were determined using MS and NMR spectral analyses, which provided valuable insights into the unique glycosidic composition of I. alba seeds.

Four new resin glycosides from Ipomoea muricata seeds: muricatins XIV-XVII.

Ipomoea muricata (L.) Jacq. seeds (Convolvulaceae) are used as a traditional laxative and carminative medicine. Muricatins XIV (1), XV (2), XVI (3), and XVII (4), were isolated from I. muricata seeds as four new resin glycosides, along with seven known compounds, three of which were isolated for the first time as natural products; their structures were determined using MS and NMR spectroscopy. Compounds 1-4 are macrolactones (jalapins); the sugar moieties of 1, 2, and 4 are partially acylated with 2S-methylbutyric acid, while that of 3 is esterified with 2S-methylbutyric and 2S-methyl-3S-hydroxybutyric acids. In addition, the antiviral activities of the seven compounds obtained in this study, together with five known compounds obtained in our previous study into resin glycosides from I. muricata seeds, were evaluated against herpes simplex virus type 1 (HSV-1); their cytotoxicities against HL-60 human promyelocytic leukemia cells were also investigated. All examined jalapins exhibited similar or slightly weaker anti-HSV-1 activities than acyclovir, the positive control; however, the glycosidic acid of 4 was inactive, while its methyl ester was weakly active. On the other hand, cytotoxicity testing against HL-60 cells showed similar results to those observed during anti-HSV-1 activity testing, with the exception that one jalapin was less active.

Cyclic sulfoxides garlicnins B2, B3, B4, C2, and C3 from Allium sativum.

Several novel sulfides, called garlicnins B2 (1), B3 (2), B4 (3), C2 (4), and C3 (5), were isolated from acetone extracts of garlic, Allium sativum L. and characterized. These garlicnins are capable of suppressing M2 macrophage activation and they have a novel skeleton of cyclic sulfoxide. The structures of the former 3 and latter of 2 were deduced to be 2-(sulfenic acid)-5-(allyl)-3,4-dimethyltetrahydrothiophene-S-oxides and 2-(allyldithiine)-5-(propenylsulfoxide)-3,4-dimethyltetrahydrothiophene-S-oxides, respectively. The mechanism of the proposed production of these compounds is discussed. The identification of these novel sulfoxides from garlic accumulates a great deal of new chemistry in the Allium sulfide field, and future pharmacological investigations of these compounds will aid the development of natural, healthy foods and anti-cancer agents that may prevent or combat disease.