Feras Q. Alali

Muricoreacin and murihexocin C, mono-tetrahydrofuran acetogenins, from the leaves of annona muricata in honour of professor G. H. Neil Towers 75th birthday

Bioactivity-directed fractionation of the leaves of Annona muricata L. (Annonaceae) resulted in the isolation of two new Annonaceous acetogenins, muricoreacin (1) and murihexocin C (2). Compounds 1 and 2 showed significant cytotoxicities among six human tumor cell lines with selectivities to the prostate adenocarcinoma (PC-3) and pancreatic carcinoma (PACA-2) cell lines.

UNUSUAL BIOACTIVE ANNONACEOUS ACETOGENINS FROM GONIOTHALAMUS GIGANTEUS

Abstract Pyranicin (1) and pyragonicin (2) are the first mono-tetrahydropyran annonaceous acetogenins, and goniotrionin (3) possesses an unusual hydroxylated-allylic moiety. 1–3 were isolated from the bark of Goniothalamus giganteus using activity-directed fractionation with the brine shrimp lethality test. Both 1 and 2 are selectively cytotoxic against the pancreatic cell line (PACA-2) in a panel of six human solid tumor cell lines with 1 showing ten times the potency of adriamycin, while 3 showed more potent selectivity against the breast cell line (MCF-7).

THREE NEW BIOACTIVE BIS-ADJACENT THF-RING ACETOGENINS FROM THE BARK OF ANNONA SQUAMOSA

Continuing work on the bioactivity-directed fractionation of the bark of Annona squamosa has resulted in the discovery of three new Annonaceous acetogenins, (2,4-cis and trans)-squamolinone (1), (2,4-cis and trans)-9-oxoasimicinone (2), and bullacin B (3). Compounds 1-3 are all adjacent bis-THF ring acetogenins with 2 representing the first bis-ring acetogenin to contain a carbonyl along its aliphatic chain. Compound 3 was selectively cytotoxic in a panel of six human tumor cell lines with a potency of nearly a million times that of adriamycin against the MCF-7 (human breast adenocarcinoma) cell line.

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.

Mono-THF ring annonaceous acetogenins from Annona squamosa

Continuing work on the bark of Annona squamosa Rich. (Annonaceae), directed by the brine shrimp lethality test (BST), has resulted in the isolation of three new Annonaceous acetogenins, 4-deoxyannoreticuin, cis-4-deoxyannoreticuin, and (2,4-cis and trans)-squamoxinone. The first two are additional examples of acetogenins isolated from this plant species which contain the unusual feature of an oxygen functionality at the C-9 position. They have a hydroxylated mono-THF ring with respective threo/trans/threo and threo/cis/threo relative stereochemistries. The latter compound is a ketolactone mixture which has the same relative stereochemistry around the THF ring and the same spatial relationship between the THF ring and the hydroxyl group along the aliphatic chain as 4-deoxyannoreticuin, but is two methylene units longer. Additionally, the isolated hydroxyl group is at C-11, while the THF ring starts at C-17, instead of at C-9 and C-15, respectively, as for the first two compounds. All three compounds showed moderate, but significant, cytotoxicities against a panel of six human tumor cell lines with (2,4 cis and trans)-squamoxinone showing promising selectivity against the pancreatic cell line (PACA-2).

4-deoxyannomontacin and (2,4-cis and trans)-annomontacinone, new bioactive mono-tetrahydrofuran annonaceous acetogenins from Goniothalamus giganteus

4-Deoxyannomontacin (1) and a mixture of (2,4-cis and trans)-annomontacinone (2), new bioactive mono-tetrahydrofuran (THF) gamma-lactone and keto-lactone acetogenins, respectively, as well as five known mono-THF acetogenins [xylomaticin, longifolicin, longicoricin, (2,4-cis and trans)-gigantetrocinone, and (2,4-cis and trans)-gigantetroneninone], were isolated from the bark of Goniothalamus giganteus (Annonaceae) by activity-directed fractionation using the brine shrimp lethality test (BST). The structures were elucidated based on spectroscopic and chemical methods. The absolute stereochemistries of 1 and 2 were determined by the advanced Mosher ester method and by circular dichroism (CD). Determination of the absolute stereochemistry at C-10 as R for 1 is the first example of the direct determination of the absolute stereochemistry of a carbinol position isolated from other functional groups in the annonaceous acetogenins. 1 and 2 showed selective and potent cytotoxicities to certain human tumor cell lines and were comparable to the activity of rotenone against yellow fever mosquito larvae.

Glabracins A and B, two new acetogenins from Annona glabra

Two new bioactive bis-THF Annonaceous acetogenins, glabracins A (1) and B (2), and two previously known acetogenins, javoricin (3) and bullatanocin (4), have been isolated from the leaves of Annona glabra by activity-directed fractionation using the brine shrimp lethality test (BST). The structures of 1 and 2 were elucidated based on spectroscopic and chemical methods, and the absolute stereochemistries were partially determined by the advanced Mosher ester method. 1 and 2 showed selective cytotoxicities to certain human tumor cell lines, and 1 was significantly more potent although 1 and 2 differ only in the stereochemistry of their vicinal diols at C-23/24.

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.

Mono-tetrahydrofuran acetogenins from Goniothalamus giganteus.

Goniotetracin and a mixture of (2,4-cis and trans)-gonioneninone, new, bioactive, mono-tetrahydrofuran (THF) gamma-lactone and ketolactone acetogenins, were isolated from the bark of Goniothalamus giganteus (Annonaceae) by activity-directed fractionation using the brine shrimp lethality test (BST). The structures were elucidated based on spectroscopic and chemical methods. Their absolute stereochemistries were determined by the advanced Mosher ester method. Both showed selective and significant cytotoxicities, comparable to the potency of adriamycin, to the human pancreatic tumour cell line (PACA-2), while goniotetracin and goniothalamicin were comparable to the activity of rotenone against yellow fever mosquito larvae.

Annodienin and Jahnonacin: New Bioactive Nontetrahydrofuran Annonaceous Acetogenins from the Twigs of Annona Jahnii

Abstract Annodienin (1) and jahnonacin (2), two new bioactive non-tetrahydrofuran Annonaceous acetogenins, have been isolated from the EtOH extract of the twigs of Annona jahnii Saff., using fractionation directed by brine shrimp lethality. These new compounds are unsaturated acetogenins and have a diol system. Compound 1 bears two double bonds in the aliphatic chain. The structures were elucidated by spectral analyses of the parent compounds and/or simple chemical derivatives, especially by employing 1H-NMR and 2D-NMR experiments. These acetogenins showed selective cytotoxicities, with potencies similar to adriamycin, among six human solid tumor cell lines.