The Antiproliferative Activity and NO Inhibition of -Clerodane Diterpenoids from in RAW 264.7 Macrophages.

In this study, nine -clerodane-type diterpenoids (-) were isolated from the dichloromethane extract of Bedolla & Zamudio leaves. Compounds - were new natural products, and - were acetone artifacts. In addition, four -clerodanes diterpenoids (-) previously described from different sources and six triterpenoids-identified as 3β,20,25-trihydroxylupane, oleanolic acid, 3β--acetyl-oleanolic acid, ursolic acid, 3β--acetyl-betulinic acid, and 3β,28--diacetyl-betulin-were isolated.

Structure, Absolute Configuration, Antiproliferative and Phytotoxic Activities of Icetexane and Abietane Diterpenoids from and Chemotaxonomic Implications.

From the aerial parts of Zamudio and Bedolla, three new icetexane-type diterpenoids were isolated. Their structures were established through spectroscopic methods and named the following: salvicarranzanolide (), 19-deoxo-salvicarranzanolide () and 19-deoxo-20-deoxy-salvicarranzanolide (). In addition, the known icetexane-type diterpenoids, 6,7,11,14-tetrahydro-7-oxo-icetexone (), -icetexone (), 19-deoxo--icetexone (), icetexone (), 19-deoxo-icetexone () and 7α-acetoxy-6,7-dihydroicetexone (), were also isolated, along with the abietanes sessein () and ferruginol ().

Structural Elucidation of Malonylcommunol and 6β-Hydroxy--communic Acid, Two Undescribed Diterpenes from . First Examples of Labdane Diterpenoids from a Mexican Species.

The aerial parts of afforded two undescribed labdane diterpenoids and (malonylcommunol and 6β-hydroxy--communic acid) along with two known labdane diterpenoids, -communic acid () and -communol (). Additionally, seven known metabolites were also isolated; two isopimarane diterpenoids and , two sesquiterpenoids identified as β-eudesmol () and cryptomeridiol (), and three aromatic compounds identified as phthalic acid (), a mixture of tyrosol fatty acid esters () and the flavone salvigenine (). While compounds compounds - showed significant inhibition of yeast α-glucosidase, compounds , and had no anti-inflammatory activity in the edema model induced by TPA.

Crystal structure of ochraceolide A isolated from (Turcz.) Lundell.

The title compound, CHO [systematic name: 6a,6 b,8a,9a,12a,14b)-4,4,6a,6;b,8a,14b-hexa-methyl-12-methyl-eneicosa-hydro-3-phenanthro[1',2':6,7]indeno-[2,1-]furan-3,11(2)-dione], is a triterpene lactone, which was isolated from di-chloro-methane extract of (Turcz.) Lundell (celastraceae) stem bark. The compound has a lupane skeleton and consists of four fused six-membered rings and two five-membered rings.

Structure, Absolute Configuration, and Antiproliferative Activity of Abietane and Icetexane Diterpenoids from Salvia ballotiflora.

From the aerial parts of , eleven diterpenoids were isolated; among them, four icetexanes and one abietane (-) are reported for the first time. Their structures were established by spectroscopic means, mainly ¹H- and C-NMR, including 1D and 2D homo- and hetero-nuclear experiments. Most of the isolated diterpenoids were tested for their antiproliferative, anti-inflammatory, and radical scavenging activities using the sulforhodamine B assay on six cancer cell lines, the TPA-induced ear edema test in mice, and the reduction of the DPPH assay, respectively.

Antidiarrheal Thymol Derivatives from Ageratina glabrata. Structure and Absolute Configuration of 10-Benzoyloxy-8,9-epoxy-6-hydroxythymol Isobutyrate.

Chemical investigation of the leaves from Ageratina glabrata yielded four new thymol derivatives, namely: 10-benzoyloxy-8,9-dehydro-6-hydroxythymol isobutyrate (4), 10-benzoyloxy-8,9-dehydrothymol (5), 10-benzoyloxythymol (6) and 10-benzoyloxy-6,8-dihydroxy-9-isobutyryl-oxythymol (7). In addition, (8S)-10-benzoyloxy-8,9-epoxy-6-hydroxythymol isobutyrate (1), together with other two already known thymol derivatives identified as 10-benzoyloxy-8,9-epoxy-6-methoxythymol isobutyrate (2) and 10-benzoyloxy-8,9-epoxythymol isobutyrate (3) were also obtained. In this paper, we report the structures and complete assignments of the ¹H and (13)C-NMR data of compounds 1-7, and the absolute configuration for compound 1, unambiguously established by single crystal X-ray diffraction, and evaluation of the Flack parameter.

ent-Kaurene Glycosides from Ageratina cylindrica.

The aqueous extract of the leaves of Ageratina cylindrica afforded six new ent-kaurenoic acid glycosides together with the known diterpenoid paniculoside V, the flavonoid astragalin, chlorogenic acid, and L-chiro-inositol. The structures were elucidated mainly by NMR and MS methods, and the absolute configuration was established by vibrational circular dichroism spectroscopy. The new compounds showed moderate antiprotozoal activity against Entamoeba histolytica and Giardia lamblia trophozoites.

Vibrational circular dichroism (VCD), VCD exciton coupling, and X-ray determination of the absolute configuration of an α,β-unsaturated germacranolide.

The absolute configuration of was deduced by vibrational circular dichroism together with the evaluation of the Flack and Hooft X-ray parameters. Vibrational circular dichroism exciton coupling, using the carbonyl group signals, confirmed the absolute configuration of . In addition, sodium borohydride reduction of the 11,13-double bond of 6-epi-desacetyllaurenobiolide () yields an almost equimolecular mixture of C11 epimers, while reduction of the same double bond of 6-epi-laurenobiolide () provided almost exclusively the (11S) diastereoisomer .

Cytotoxic diterpenes from roots of Crossopetalum gaumeri, a Celastraceae species from Yucatan Peninsula.

Four new diterpenes, crossogumerins A-D (1-4) along with six known ones (5-10) were isolated from the root bark of Crossopetalum gaumeri, an endemic medicinal plant from the Yucatan Peninsula. Their structures were elucidated on the basis of 1D and 2D NMR techniques, including HMQC, HMBC, and ROESY experiments. Compounds 1-5, 8-10 were evaluated for cytotoxicity against HeLa (carcinoma of the cervix) and Hep-2 (lung carcinoma) human tumor cells lines and against normal Vero cells (African green monkey kidney) in lag and log phase of growth.

Structure, absolute configuration, and antidiarrheal activity of a thymol derivative from Ageratina cylindrica.

The leaves of Ageratina cylindrica afforded a thymol derivative that was characterized by physical and spectroscopical methods as (8S)-8,9-epoxy-6-hydroxy-l0-benzoyloxy-7-oxothymol isobutyrate (1). The absolute configuration of 1 was established as 8S by vibrational circular dichroism spectroscopy in combination with density functional theory calculations and by evaluation of the Flack and Hooft X-ray parameters. Compound 1 showed weak antiprotozoal activity against Entamoeba histolytica and Giardia lamblia trophozoites and a high inhibitory effect on hyperpropulsive movement of the small intestine in rats.

A C-Glycosylflavone from Piper ossanum, a Compound Conformationally Controlled by CH/π and Other Weak Intramolecular Interactions.

The structure of the known 2''-O-α-rhamnosyl-4''-O-methylvitexin (apigenin-8-C-α-rhamnosyl-(1→2)-β-4-O-methylglucopyranoside), isolated from the leaves of Piper ossanum, was revised to acacetin-8-C-neohesperidoside (acacetin-8-C-α-rhamnosyl-(1→2)-β-glucopyranoside or 2''-O-α-rhamnosyl-4'-O-methylvitexin) (1). The NMR data and theoretical calculations established the preferred conformation of 1, which is controlled by CH/π interactions. This phenomenon explains the unusual chemical shifts of some protons in the molecule, besides other weak intramolecular interactions such as the anomeric effect, the Δ2 effect, and several hydrogen bonds.

The tropical brown alga Lobophora variegata: a source of antiprotozoal compounds.

Lobophora variegata, a brown alga collected from the coast of the Yucatan peninsula, Mexico, was studied for antiprotozoal activity against Giardia intestinalis, Entamoeba histolytica and Trichomonas vaginalis. The whole extract showed the highest activity against T. vaginalis, with an IC(50) value of 3.

Conformational properties of the germacradienolide 6-epidesacetyllaurenobiolide by theory and NMR analyses.

Knowing the conformational properties of 1(10),4-cyclodecadiene gamma-lactones is important because of the biogenetic and evolutionary implications on the different groups of sesquiterpene lactones. Despite their importance, there are no physicochemical data on the conformational dynamic and the potential energy surface associated with the conformational changes of the cyclodecadiene ring. Fischer's biogenetic theory on the origin of ambrosanolides and helenanolides has support in the results presented since the conformers that yield two groups of sesquiterpene lactones coexist in solution as demonstrated by dynamic NMR experiments.

Chemical constituents of Pithecellobium albicans.

A new ent-kaurane diterpene glycoside identified as (-)19-beta-D-glucopyranosyl 6,7-dihydroxy kaurenoate, was isolated from the seeds of Pithecellobium albicans. The structure of the new compound was established by spectral data.

21beta-Hydroxy-oleanane-type triterpenes from Hippocratea excelsa.

Stem bark of Hippocratea excelsa afforded six pentacyclic triterpenes, five oleanane and one ursane types. They were identified as 11beta,21beta-dihydroxy-olean-12-ene-3-one (2), 3alpha,11alpha,21beta-trihydroxy-olean-12-ene (3), 3alpha,21beta-dihydroxy-11alpha-methoxy-olean-12-ene (4), 3alpha,21beta-dihydroxy-olean-9(11),12-diene (5), 3alpha,21beta-dihydroxy-olean-12-ene (6) and 3alpha,21beta-dihydroxy-11alpha-methoxy-urs-12-ene, isolated as its diacetate derivative (7), as well as 3alpha,21beta-dihydroxy-olean-12-ene (1) previously isolated from the root bark. The known alpha- and beta-amyrin, oleanoic and ursolic acids, trans-polyisoprene, and the ubiquitous beta-sitosterol were also isolated.

Antiprotozoal activity of Senna racemosa.

Methanol extracts of leaves, roots and bark of Senna racemosa (Mill.) H.S.

Antigiardial activity of triterpenoids from root bark of Hippocratea excelsa.

Two new triterpenoids, 21 beta-hydroxyolean-12-en-3-one (1) and a seco-dinor derivative of pristimerine named dzununcanone (2), were isolated from the root bark of Hippocratea excelsa. Their structures were assigned on the basis of spectroscopic evidence, mainly 1H and 13C 1D and 2D NMR including DEPT, COSY, ROESY, HSQC, and HMBC experiments, as well as EIMS and HREIMS. The known 21alpha-hydroxy-3-oxofriedelane (3), a compound new to the species, and the known methide quinones pristimerine (4) tingenone (5), and xuxuarine Ebeta (7) were also isolated.

Antinociceptive activity of 3-O-beta-d-glucopyranosyl-23,24-dihydrocucurbitacin F from Hintonia standleyana (Rubiaceae).

Oral administration of a MeOH-CH(2)Cl(2) (1:1) extract of the stem bark of Hintonia standleyana (HSE) produced a dose-dependent antinociceptive effect when tested in mice using the writhing (150-750 mg/kg) and the hot-plate (150-600 mg/kg) models. From the active extract 3-O-beta-d-glucopyranosyl-23,24-dihydrocucurbitacin F (GDHCF), 5-O-[beta-d-apiofuranosyl-(1-->6)-beta-d-glucopyranosyl]-7-methoxy-3',4'-dihydroxy-4-phenylcoumarin (AG4-PC) and desoxycordifolinic acid (DCA) were isolated. GDHCF (10-100 mg/kg, p.

Triterpenoid oligoglycosides from the sea cucumber Stichopus parvimensis.

Two new holostan-type triterpenoid oligoglycosides, named parvimosides A (1) and B (2), were isolated from the warty sea cucumber Stichopus parvimensis (syn. Parastichopus parvimensis). Their structures and total assignments of the proton and carbon signals were established on the basis of spectral evidence, mainly 1H and 13C 1D and 2D NMR spectroscopy including DEPT, COSY, TOCSY, NOESY/ROESY, HMQC/HSQC, and HMBC experiments, as well as FABMS.