Monotetrahydrofuran annonaceous acetogenins from the seeds of Annona squamosa

Three new monotetrahydrofuran annonaceous acetogenins, Annosquamins A–C (1–3) were isolated from the 95% EtOH extract of Annona squamosa seeds, in addition to the known compounds, solamin, annotemoyin-1, uvariamicin-II, uvariamicin-III. Their structures were elucidated by spectroscopic analysis and the relative configurations of bearing tetrahydrofuran rings were established by comparing NMR data with model compounds.     

Annonaceous acetogenins: Precursors from the seeds of Annona squamosa

From the less polar fractions of an Annona squamosa (Annonaceae) seeds extract, four new annonaceous acetogenins, dieposabadelin (1), squamocenin (2), lepirenin (3) and dotistenin (4), were isolated, along with sixteen known acetogenins: corepoxylone, diepomuricanins A and B, dieporeticenine, tripoxyrollin, bullatencin, glabrencin B, reticulatains-1, -2, uvariamicins I, II, III, erythrosolamin, annotemoyin-1 and -2, and solamin. Fourteen are reported for the first time in this species.     

Three cytotoxic Annonaceous acetogenins from the seeds of Annona squamosa

Three new Annonaceous acetogenins, squamocin-IV (1), squamocin-V (2) and squamoxinone-E (3), together with seven other known Annonaceous acetogenins (4–10) were isolated from the seeds of Annona squamosa. The structures of all of the isolates were established and characterized through spectral and chemical methods. The new Annonaceous acetogenins 1–3 were evaluated for their cytotoxicity against the Hep-G2, SMMC-7721, BEL-7402, BGC-803 and H460 human cancer cell lines. Compound 3 exhibited the best cytotoxic activity, with IC₅₀ values of 0.103, 0.687, 4.19, 0.43 and 6.56 μg/mL, respectively for the cell lines above; meanwhile, Compound 1 showed selective cytotoxic activity against H460, with an IC₅₀ value of 0.049 μg/mL. The first mono-ACG (2) composed of 38 carbons was discovered.     

Bullatencin, 4-deoxyasimicin, and the uvariamicins: additional bioactive Annonaceous acetogenins from Annona bullata Rich. (Annonaceae).

Additional bioactive Annonaceous acetogenins have been isolated from the EtOH extract of the bark of Annona bullata Rich. by bioactivity-directed fractionation using lethality to brine shrimp. These acetogenins include bullatencin, a new single tetrahydrofuran acetogenin having a double bond in the hydrocarbon chain; 4-deoxyasimicin, a new adjacent bis-tetrahydrofuran acetogenin; and the uvariamicins, an isomeric mixture of four single tetrahydrofuran acetogenins showed selective cytotoxicities for certain human solid tumor cell lines comparable to or better than adriamycin.     

Alkaloids from leaves of Annona salzmannii and Annona vepretorum (Annonaceae)

Phytochemical investigation of the leaves of Annona salzmannii and Annona vepretorum (Annonaceae) led to the identification of seven aporphine alkaloids, anonaine, asimilobine, norcorydine, lanuginosine, liriodenine, lysicamine and oxonantenine, as well as, 1,3,6,6-tetramethyl-5,6,7,8-tetrahydro-isoquinolin-8-one and vomifoliol. Liriodenine, anonaine, asimilobine and norcorydine were found in A. salzmannii, while liriodenine, oxonantenine, lanuginosine, lysicamine, vomifoliol and 1,3,6,6-tetramethyl-5,6,7,8-tetrahydro-isoquinolin-8-one were found in A. vepretorum. All these compounds are being described for the first time in the leaves of A. salzmannii and A. vepretorum. This is the first report of 1,3,6,6-tetramethyl-5,6,7,8-tetrahydro-isoquinolin-8-one in the Annonaceae. The NMR data for oxonantenine, lanuginosine and lysicamine were reviewed.     

Annonaceous acetogenins from the leaves of Annona montana

A novel Annonaceous acetogenin, montanacin F, with a new type of terminal lactone unit, was isolated from the leaves of Annona montana. Its structure was determined on the basis of spectral evidences and chemical methods, and a possible biosynthetic pathway was discussed. In addition, the cytotoxicity of montanacin F was evaluated in vitro against Lewis lung carcinoma (LLC) tumor cell lines. Furthermore, the previously isolated cytotoxic acetogenin annonacin against LLC was examined for in vivo antitumor activity with LLC tumor cells.     

Novel cytotoxic monotetrahydrofuranic Annonaceous acetogenins from Annona montana

Four new monotetrahydrofuranic Annonaceous acetogenins, montalicins G (1) and H (2) and monlicins A (3) and B (4), and two new linear acetogenins, (+)-monhexocin (5) and (-)-monhexocin (6), as well as three known compounds, murisolin (7), 4-deoxyannomontacin (8), and muricatacin (9), were isolated from the seeds of Annona montana by high performance liquid chromatographic (HPLC) method. The absolute stereochemical structures of new isolates were elucidated and characterized by spectral and chemical methods. Interestingly, these compounds show special cytotoxicity against human hepatoma cells, Hep G2.     

Two bioactive mono-tetrahydrofuran acetogenins, annoglacins A and B, from Annona glabra

Two new bioactive mono-THF Annonaceous acetogenins, annoglacins A and B, have been isolated from the fractionated ethanolic extracts of the leaves of Annona glabra, directing the fractionation with the brine shrimp lethality test (BST). Their structures were elucidated based on spectroscopic and chemical methods and the absolute stereochemistries were determined by the advanced Mosher ester method. Annoglacins A and B were selectively 1000 and 10,000 times, respectively, more potent than adriamycin against the human breast carcinoma (MCF-7) and pancreatic carcinoma (PACA-2) cell lines in our panel of six human solid tumor cell lines.     

Squamocin-O(1) and squamocin-O(2), new adjacent bis-tetrahydrofuran acetogenins from the seeds of Annona squamosa

Two bis-tetrahydrofuran acetogenins, squamocin-O(1) (1) and squamocin-O(2) (2), were isolated from a MeOH extract of seeds of Annona squamosa L. Their structures were determined by spectral means including precursor-ion scanning mass spectral analysis for their aminal derivatives. The configurations at the oxymethine chiral centers were assigned as 12R,15R,16R,19R,20R,23R,24S,28S,36S for 1 and 12S,15R,16R,19R,20R,23R,24S, 28S,36S for 2, based on 1H NMR analysis of their Mosher's ester derivatives and CD data.     

Annojahnin from Annona jahnii: a possible precursor of mono-tetrahydrofuran acetogenins

A new cytotoxic Annonaceous acetogenin, annojahnin (1), was isolated from the twigs of Annona jahnii (Annonaceae) by bioactivity-directed fractionation using lethality to brine shrimp. Compound 1 represents an unusual type of C–37 Annonaceous acetogenin, lacking either tetrahydrofuran (THF) or epoxide rings, bearing a keto group at C–10, and possessing a double bond located two methylenes away from a vicinal diol. The structure and absolute configuration of 1 were elucidated by ¹H and ¹³C NMR, COSY, and single-relayed COSY and from chemical derivatives. 4-Deoxy-18/21-trans-annomontacin 10-one (4) and 4-deoxy-18/21-cis-annomontacin-10-one (5), two semisynthetic mono-THF acetogenins, were prepared from 1 by reactions that mimic the biogenetic pathways. These acetogenins showed selective cytotoxicities, comparable or superior to adriamycin, among six human solid tumor cell lines. Reduction of the 10-keto of 1, to the racemic 10-OH derivative (3), retained the bioactivities as did the conversion of 1 to 4 and 5.     

Chemical constituents from the bark of Annona salzmannii (Annonaceae)

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Highlights? Bark of Annona salzmannii yielded sesquiterpenes, steroids, and isoquinoline alkaloids. ? Isoquinoline alkaloids are the chemotaxonomic marker of the genus Annona. ? The NMR data for reticuline (12) were revised. ? Selin-11-en-4α-ol (3) is reported for the first time in the genus Annona.     

Isoquinoline alkaloids from the leaves of Annona leptopetala (Annonaceae)

The phytochemical investigation of the leaves of Annona leptopetala (R. E. Fr.) H. Rainer led to the characterization of tetrahydroprotoberberine corypalmine, and four aporphine (laurotetanine, anonaine, norannuradhapurine and nornuciferine) alkaloids. The structures were established after analysis of their NMR spectral data including 2D NMR experiments. This is the first report of laurotetanine and nornuciferine in A. leptopetala as well as norannuradhapurine in the genus Annona. The ¹³C NMR data of the natural alkaloid norannuradhapurine are reported here for the first time, and the NMR data for the compound corypalmine are reviewed.     

Two cyclopeptides from the seeds of Annona cherimola

Bioassay-guided fractionation of cytotoxic of methanol extract of the seeds of Annona cherimola provided two novel cyclic peptides, cherimolacyclopeptide E (1) and cherimolacyclopeptide F (2), which exhibited significant cytotoxic activity against the KB (human nasopharyngeal carcinoma) cell culture system. The peptide 1 and 2 were elucidated by MS/MS fragmentation experiments using a Q-TOF mass spectrometer equipped with an ESI source, extensive 2D NMR analyses and chemical degradation.     

Glaucacyclopeptide A from the seeds of Annona glauca

The seeds of Annona glauca furnished two cyclopeptides one of which is novel. The structure was elucidated on the basis on mass spectrometry, 2D NMR methods and amino acids analysis.     

A new species of Annona (Annonaceae) from the northeastern Guayana Shield

Annona prevostiae, a new species from the northeastern margin of the Guayana Shield, is described and illustrated.     

Distribution and host range of Bephratelloides cubensis Ashmead (Hymenoptera: Eurytomidae) in Mexico

The annona fruit borer wasp Bephratelloides cubensis Ashmead was recorded for the first time damaging "ilama" fruits Annona diversifolia (Anonaceae) in Coatlan del rio, Morelos, Cacahuamilpa and El Ocotillo, Guerrero, Mexico. Geographical distribution, hosts and damage are mentioned.     

Biology and behavior of the seed borer wasp Bephratelloides cubensis ashmead (Hymenoptera: Eurytomidae)

The soursop Annona muricata is an important fruit for national market, and for exportation, but the crop is affected by pests and diseases. The seed borer wasp Bephratelloides cubensis Ashmead is the pest that produces the highest damage to the crop in Mexico. Sixty percent of damaged fruits and 5-50 seeds per fruit have been registered, with 25% reduction in yield. In Nayarit, Mexico, 100% of damaged fruits were recorded. In this State, an experiment with soursop was conducted to study the life cycle under field conditions and to determine diurnal behavior of the female of B. cubensis. The highest activity of the wasp was observed between 12:00h and 13:00h (35oC, 54% RH and 409.34 luxes). Females oviposited in fruits with a diameter of 3.1-7.6 cm. Larvae of B. cubensis developed five instars, adults survived no longer than 22 days, and female survived longer than males; they lived 22 and 15 days, respectively. Life cycle of B. cubensis varied from 69 to 122 days.     

Purification and characterization of a lectin from Annona coriacea seeds

A novel lectin, denominated ACLEC, was isolated from Annona coriacea seeds, belonging to the Annonaceae family. The lectin presented one protein band in SDS-PAGE of 14 kDa. Of the sugars tested, Dglucose and D-mannose were the best inhibitors. A search sequence database showed that ACLEC had homology with other plant lectins, belonging to leguminous lectin family.     

Isolation and characterization of a lectin from Annona muricata seeds

A lectin with a high affinity for glucose/mannose was isolated from Annona muricata seeds (Annonaceae) by gel filtration chromatography on Sephacryl S-200, ion exchange chromatography on a DEAE SP-5 PW column, and molecular exclusion on a Protein Pak Glass 300 SW column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (PAGE) yielded two protein bands of approximately 14 kDa and 22 kDa. However, only one band was seen in native PAGE. The Mr of the lectin estimated by fast-performance liquid chromatography-gel filtration on Superdex 75 was 22 kDa. The lectin was a glycoprotein with 8% carbohydrate (neutral sugar) and required divalent metal cations (Ca2+, Mg2+, and Mn2+) for full activity. Amino acid analysis revealed a large content of Glx, Gly, Phe, and Lys. The lectin agglutinated dog, chicken, horse, goose, and human erythrocytes and inhibited the growth of the fungi Fusarium oxysporum, Fusarium solani, and Colletotrichum musae.     

Chemical constituents from the leaves and branches of Annona coriacea Mart. (Annonaceae)

The phytochemical investigation of the leaves and branches of Annona coriacea Mart. (Annonaceae) led to the isolation and characterization of eight compounds: five isoquinoline-derived alkaloids, including pukateine (1), liriodenine (4), anonaine (5), obovanine (6), and norisocorydine (7); one terpene lactone known as loliolide (3); one benzoic acid derivative, 2-methoxybenzoic acid (2), and 3,4,5-trimethoxyphenol (8). All compounds, except liriodenine, are being described for the first time in the species A. coriacea, and their chemophenetics relationships were discussed. The structures were elucidated by extensive analyses of 1D and 2D NMR (COSY, HSQC, and HMBC) spectroscopy in combination with MS, and the data were compared with literature values. The NMR dataset of pukateine and obovanine was reviewed. Our results showed that A. coriacea is a typical species of the Annonaceae family and an important source of aporphine alkaloids with chemophenetic relationships with Xylopia, Duguetia, Guatteria, Artabotrys, and Goniothalamus genera.