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.

Production of distinct labdane-type diterpenoids using a novel cryptic labdane-like cluster from Streptomyces thermocarboxydus K155.

Bioinformatic mining of the Streptomyces thermocarboxydus K155 genome predicted the presence of four synthases for the production of geosmin, hopene, albaflavenone, and a type B-type A diterpenoid system like that described for labdane-related diterpenoids (LRD). The lrd cluster was comprised by an operon of four genes (lrdABDC). This cluster seemed to be silent in the wild-type strain, as neither labdane nor terpene-like compounds were detected by UPLC-TOF-MS and GC-MS analyses in both culture supernatants and mycelial extracts.

Exo-Metabolites of -Nodulating Rhizobial Strains.

Rhizobia are able to convert dinitrogen into biologically available forms of nitrogen through their symbiotic association with leguminous plants. This results in plant growth promotion, and also in conferring host resistance to different types of stress. These bacteria can interact with other organisms and survive in a wide range of environments, such as soil, rhizosphere, and inside roots.

The structure of (E)-biformene synthase provides insights into the biosynthesis of bacterial bicyclic labdane-related diterpenoids.

The labdane-related diterpenoids (LRDs) are a large group of natural products with a broad range of biological activities. They are synthesized through two consecutive reactions catalyzed by class II and I diterpene synthases (DTSs). The structural complexity of LRDs mainly depends on the catalytic activity of class I DTSs, which catalyze the formation of bicyclic to pentacyclic LRDs, using as a substrate the catalytic product of class II DTSs.

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.

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.

Antifeedant activity of anticopalic acid isolated from Vitex hemsleyi.

The known labdane-type diterpenoids anticopalic acid (1) and 3 beta-hydroxyanticopalic acid (2) were isolated from extracts of the aerial parts of Vitex hemsleyi Briq. (Labiatae). The acid 1 showed an antifeedant, dose-dependent activity against Spodoptera frugiperda (J.

Antisecretory activity from the flowers of Chiranthodendron pentadactylon and its flavonoids on intestinal fluid accumulation induced by Vibrio cholerae toxin in rats.

Ethnopharmacological Relevance: The flowers of Chiranthodendron pentadactylon Larreat. (Sterculiaceae) has been traditionally used as folk medicine in Mexico for the treatment of gastrointestinal disorders such as diarrhea and dysentery.

Aim Of The Study: This study aimed to assess the antisecretory activity which supports the therapeutic use of Chiranthodendron pentadactylon and its flavonoids to treat diarrhea.

Pensteminoside, an unusual catalpol-type iridoid from Penstemon gentianoides HBK (Plantaginaceae).

From the MeOH and ethyl acetate extracts of aerial parts of Penstemon gentianoides HBK (Plantaginaceae) an unusual iridoid of the catalpol-type, was isolated and characterized as pensteminoside: (8-O-trans-cinnamoyl, 6-hydroxy, 1-[beta-D-glucopyranoside-6'-O-((4''-hydroxy)-cinnamoyl)]-catalpol) was isolated, along with the known iridoids: plantarelanoside and globularisicin, the flavone: luteolin and diosmetin, as well the phenylpropanoids, verbascoside and martynoside. Their structures were established by 1D and 2D NMR spectroscopic analyses.

Abietane diterpenoids from the roots of some Mexican Salvia species (Labiatae): chemical diversity, phytogeographical significance, and cytotoxic activity.

From the roots of some Mexican Salvia species, classified in subgenus Jungia, several diterpenoids belonging to abietane (i.e., 3-7), salvifolane (9-->20,10-->6)-diabeoabietane) (i.

Chemical composition and anti-inflammatory activity of the volatile fractions from the bark of eight Mexican Bursera species.

The volatile fractions from the bark of eight species of Mexican Bursera were obtained using steam distillation and were subjected to tandem GC-MS analysis for identification of the main constituents. The most abundant components of steam volatiles were monoterpenoids from which alpha-terpineol, terpinen-4-ol, alpha-thujene, linalool and limonene were most frequently isolated. A series of sesquiterpenes and long-chain hydrocarbons were isolated and identified from the barks of some of the studied species .

Rearranged icetexane diterpenoids from the roots of Salvia thymoides (Labiatae).

From the roots of Salvia thymoides Benth., three new rearranged icetexane diterpenoids (2-4) were isolated together with the previously described quinone tilifolidione (1). The proposed structures were established by extensive NMR analysis, including HMBC and HMQC pulse sequences.

Unsaturated diterpenoids with a novel carbocyclic skeleton from Salvia xalapensis.

Two diterpenoids with an unprecedented carbocyclic skeleton, salvixalapadiene (3) and isosalvixalapadiene (4), have been obtained from the leaves of Salvia xalapensis. The rearranged skeleton of these products may be derived biogenetically from a salvigenane precursor. In addition, two new rearranged diterpenoids (1 and 2) belonging to already known skeletons were isolated.

Antiprotozoal activity of the constituents of Teloxys graveolens.

Antiprotozoal activity-guided fractionation of a methanol extract of the aerial parts of Teloxys graveolens led to the isolation of one coumarinic acid derivative, melilotoside, and five flavonoids, pinocembrine, pinostrobin, chrysin, narcissin and rutin. Among them, melilotoside exhibited the most potent activity toward Entamoeba histolytica and Giardia lamblia (IC(50) 12.5 and 16.

Tri-nordammarane triterpenoids and neoclerodane diterpenoids from Salvia aspera (Labiatae).

From the aerial parts of Salvia aspera one new tri-nordammarane named amblyol (1) was isolated besides amblyone (2). An X-ray analysis was performed on compound 1. In addition, three known neoclerodane diterpenoids were also isolated.