Alicia B. Pomilio

Alkaloids of Datura ferox from Argentina

Chromatographic procedures (HPLC, GC-MS) are outlined in this paper for the analysis of alkaloids in poisonous Datura ferox seeds of Argentina, from which previously only quantitative analysis for scopolamine was known. Five additional tropane alkaloids are now identified as 3 alpha-tigloyloxytropane (tigloyltropeine), 3-phenylacetoxy-6 beta,7 beta-epoxytropane (3-phenylacetoxyscopine), aposcopolamine (apohyoscine), 7 beta-hydroxy-6 beta-propenyloxy-3 alpha-tropoyloxytropane, traces of 7 beta-hydroxy-6 beta-isovaleroyloxy-3 alpha-tigloyloxytropane and a pyrrolidine alkaloid, hygrine. Two new structures, 3-phenylacetoxy-6 beta,7 beta-epoxytropane (3-phenylacetoxyscopine) and 7 beta-hydroxy-6 beta-propenyloxy-3 alpha-tropolyoxytropane, are proposed on the basis of their spectra. Hyoscyamine, nicotine and tropane N-oxides were not detected in all samples studied.

Constituents of the root exudate of Avena fatua grown under far-infrared-enriched light.

The constituents of the root exudate of plantlets of wild oats (Avena fatua) grown in the greenhouse under far-IR-enriched radiation were analysed for the first time by HPTLC and capillary GC, and further separated by medium-pressure liquid chromatography (MPLC; monitored by TLC) and characterised by GC-EIMS and 1H-NMR. This combination of methodologies permitted the study of root exudates under controlled conditions and is appropriate for examining a variety of ecophysiological/environmental effects in a short time period. In this instance, the response compounds of the irradiated plantlets were identified as linear and branched alcohols, linear and branched alkanes, a bicyclic monoterpene, mono- and bicyclic sesquiterpenes, and free and esterified fatty acids. An ester, isopropyl myristate, was the main component present, although the unusual occurrence of branched compounds, sesquiterpenoids and related compounds of isoprenoid metabolism is noteworthy. The effect of far-IR-enriched light on the production of these compounds is discussed. Copyright

Sitosterol 3-O-β-D-xylopyranoside from Bauhinia candicans

Abstract A novel steroidal glycoside was isolated from aerial parts of Bauhinia candicans . Its structure was determined as sitosterol 3- O -β- D -xylopyranoside by chemical and spectral methods.

Antitumor and cytotoxic screen of 5,6,7-trisubstituted flavones from Gomphrena martiana

An in vivo antitumor screening of extracts of Gomphrena martiana indicated positive activity in the petroleum ether extract, and its further bioactivity-directed fractionation resulted in a lipophilic flavonoid fraction. Upon inoculation of various doses of 5,6,7-trisubstituted flavones on two murine tumor lines, Sarcoma 180 and Ehrlichs carcinoma, a decrease of tumor growth was observed. An in vitro KB cultured cell screen indicated cytotoxicity

Flavonoids from Erythroxylon argentinum

Abstract Quercetin 3-rutinoside, quercetin 3-α- l -rhamnoside, 7,4′-dimethylquercetin 3-rutinoside and the novel glycoside 7,4′-dimethylquercetin 3-rutinoside-5-glucoside have been identified from aerial parts of Erythroxylon argentinum .

New methylated flavones from Gomphrena martiana

Abstract Two new flavones, 3,5,6,7-tetramethoxyflavone and 3,6-dimethoxy-5,7-dihydroxyflavone together with 3,5,7-trimethoxyflavone have been identified from a whole plant extract of Gomphrena martiana .

In Vivo Long-Term Kinetics of Radiolabeled N,N-Dimethyltryptamine and Tryptamine

N,N-dimethyltryptamine (DMT), a strong psychodysleptic drug, has been found in higher plants, shamanic hallucinogenic beverages, and the urine of schizophrenic patients. The aim of this work was to gain better knowledge on the relationship between this drug and hallucinogenic processes by studying DMT behavior in comparison with tryptamine. Methods: 131I-labeled DMT and tryptamine were injected into rabbits. γ-Camera and biodistribution studies were performed. Brain uptake, plasma clearance, and renal excretion were assessed for each indolealkylamine. Results: DMT and tryptamine showed different behavior when brain uptake, residence time, and excretion were compared. Labeled DMT entered the brain 10 s after injection, crossed the blood–brain barrier, and bound to receptors; then it was partially renally excreted. It was detected in urine within 24 h after injection and remained in the brain, even after urine excretion ceased; up to 0.1% of the injected dose was detected at 7 d after injection in the olfactory bulb. In contrast, tryptamine was rapidly taken up in the brain and fully excreted 10 min after injection. Conclusion: To our knowledge, this is the first demonstration that exogenous DMT remains in the brain for at least 7 d after injection. Although labeled DMT and tryptamine behave as agonists for at least 5-hydroxytryptamine 2A receptor, 5-hydroxytryptamine 2C receptor, trace amine-associated receptor, and σ-1 putative receptor targets, binding to the latter can explain the different behavior of labeled DMT and tryptamine in the brain. The persistence in the brain can be further explained on the basis that DMT and other N,N-dialkyltryptamines are transporter substrates for both the plasma membrane serotonin transporter and the vesicle monoamine transporter 2. Furthermore, storage in vesicles prevents DMT degradation by monoamine oxidase. At high concentrations, DMT is taken up by the serotonin transporter and further stored in vesicles by the vesicle monoamine transporter 2, to be released under appropriate stimuli. Moreover, the 131I-labeling proved to be a useful tool to perform long-term in vivo studies.

7,8-Dihydroajugasterone C, norhygrine and other constituents of Nierembergia hippomanica

Abstract The new ecdysteroid-like polyhydroxyketosterol (20 R ,22 R )-2 β ,3 β ,11 α ,14 α ,20,22-hexahydroxy-5β-cholestan-6-one (7,8-dihydroajugasterone C or 7,8-dihydro-11α-hydroxyponasterone A) and the new pyrrolidine alkaloid, norhygrine, were identified as constituents of whole plants of Nierembergia hippomanica , together with the known compounds, ecdysterone, quercetin 3-O-β- d -galactopyranoside, d -mannitol, choline and tigloidine.

Complex anthocyanins from Ipomoea congesta

Abstract Six acylated anthocyanins have been isolated from the flowers of Ipomoea congesta R. Brown. One has been previously described as an acylated peonidin derivative. Three others are isomers, derived from peonidin-3-(caffeylsophoroside)-5-glucoside. The fifth was characterised as peonidin-3-(p-coumarylcaffeylsophoroside)-5-glucoside and the last as peonidin-3-(coumarylsophoroside)-5-glucoside. It is noteworthy that the anthocyanins found in this species have the same glycosidic pattern, 3-sophoroside-5-glucoside, as those reported for the cyanidin derivatives in Ipomoea cairica flowers. Acylated anthocyanin occurrence in Tubiflorae order is of chemotaxonomical value.

Alkaloids from endophyte-infected Festuca argentina.

Five loline-type alkaloids, the known lolinine, N-formylloline, loline, N-methylloline and the new 5,6-dehydro-N-acetylloline, were characterized from the pooid-grass endophyte-infected Festuca argentina. These compounds are not responsible for the toxicity of the plant, as shown upon i.p. injection into mice. Their probable phytoalexine role and chemotaxonomical significance are discussed.