Tri‐ and Bicyclic Taxoids from the Taiwanese Yew Taxus sumatrana

Five new taxoids, including a new 2(3→20)‐abeo‐taxane with a 6/10/6‐membered ring system and four 3,8‐seco‐taxanes having a 6/12‐membered ring system, were isolated from an acetone extract of the leaves and twigs of the Taiwanese yew (Taxus sumatrana, Taxaceae). The structures were established as 2α,7β,10α‐triacetoxy‐5α‐hydroxy‐2(3→20)‐abeo‐taxa‐4(20),11‐dien‐9,13‐dione ( 1 ), (3E,8E)‐2α,9,10β, 13α,20‐pentaacetoxy‐7β‐hydroxy‐3,8‐secotaxa‐3,8,11‐trien‐5‐one ( 2 ), (3E,8E)‐2α,9,10β,13α,20‐pentaacetoxy‐5α,7β‐dihydroxy‐3,8‐secotaxa‐3,8,11‐triene ( 3 ), (3E,8E)‐9,10β,13α‐triacetoxy‐2α,7β,20‐trihydroxy‐5α‐[(2E)‐cinnamoyloxy]‐3,8‐secotaxa‐3,8,11‐triene ( 4 ), and (3E,8E)‐2α,5α,7β,9,10β,13α‐hexaacetoxy‐20‐hydroxy‐3,8‐secotaxa‐3,8,11‐triene ( 5 ), respectively, on the basis 1D‐ and 2D‐NMR spectral analyses. The in vitro cytotoxic activity of compounds 1 – 5 against four human tumor cell lines, including HeLa (cervical epitheloid), WiDr (colon), Daoy (medulloblastoma), and Hep2 (liver carcinoma) tumor cells was evaluated. Whereas compounds 1 – 3 were inactive, the novel taxanes 4 and 5 showed significant cytotoxicity.     

Three New Peroxy Triterpene Lactones from Pseudolarix kaempferi

Three new 3(4),9(10)‐disecocycloartane peroxy triterpene lactones, named as pseudolarolides Q₂, T₁, and T₂ ( 1 – 3 , resp.), along with five known triterpenoids, were isolated from the seeds of Pseudolarix kaempferi Gord . Their structures were elucidated to be (9R,10R,16R,23R,25R)‐16,23‐epoxy‐9,10‐epidioxy‐3,4:9,10‐disecocycloart‐1(2)‐ene‐3,4:26,23‐diolide ( 1 ), (1R,9R,10S,16R,23S,25R)‐1,4:16,23‐diepoxy‐9,10‐epidioxy‐3,4;9,10‐disecocycloartan‐26(23)‐olid‐3‐oic acid methyl ester ( 2 ), and (1R,9R,10S,16R,23R,25R)‐1,4:16,23‐diepoxy‐9,10‐epidioxy‐3,4;9,10‐disecocycloartan‐26(23)‐olid‐3‐oic acid methyl ester ( 3 ) on the basis of spectroscopic analysis.     

A New Antifungal Cyclic Lipopeptide from Bacillus marinus B‐9987

A new cyclic lipopeptide, marihysin A ( 1 ), along with the three known cyclodipeptides cyclo(Ala‐Ile) ( 2 ), cyclo(Ala‐Leu) ( 3 ), and cyclo(Ala‐Tyr) ( 4 ), was isolated from the fermentation broth of the marine microorganism Bacillus marinus B‐9987 isolated from the tissues of rhizophere of Suaeda salsa in the intertidal zone of the Bohai Bay of P. R. China. Marihysin A ( 1 ) was established to be cyclo(Pro‐Gln‐Asn¹‐Ser‐Asn²‐Tyr‐Asn³‐β‐aminotetradecanoic acid) by spectroscopic analysis, and it exhibits broad‐spectrum but low activity against plant pathogens as determined by antifungal bioassay.     

A New Anthraquinone and Two New Tetrahydroanthraquinones from the Roots of Prismatomeris connata

A new anthraquinone, 4‐hydroxy‐1,2,3‐trimethoxy‐6‐methylanthracene‐9,10‐dione ( 1 ), and two novel tetrahydroanthraquinones, prisconnatanones A and B ( 2 and 3 , resp.), together with 15 known anthraquinones, 4 – 18 , were isolated from the roots of Prismatomeris connata. Their structures were elucidated on the basis of spectroscopic data. Compounds 1 – 18 were evaluated for their cytotoxicity against A549 and LAC human cancer cell lines. Compound 2 and the anthraquinones with free OH groups exhibited activity against the test cell lines.     

New 9,10‐Secosteroids from Biotransformations of Hyodeoxycholic Acid with Rhodococcus spp.

The biotransformations of hyodeoxycholic acid with various Rhodococcus spp. are reported. Some strains (i.e., Rhodococcus zopfii, Rhodococcus ruber, and Rhodococcus aetherivorans) are able to partially degrade the side chain at C(17) to afford 6α‐hydroxy‐3‐oxo‐23,24‐dinor‐5β‐cholan‐22‐oic acid ( 2 ; 23%) and 6α‐hydroxy‐3‐oxo‐23,24‐dinorchol‐1,4‐dien‐22‐oic acid ( 3 ; 23–30%), together with two new 9,10‐secosteroids 4 and 5 (10–45%), still bearing the partial side chain at C(17) and adopting an intramolecular hemiacetal form. In addition, the 9,10‐secosteroid 5 showed an unprecedented C(4)‐hydroxylation. The new secosteroids were fully characterized by MS, IR, NMR, and 2D‐NMR analyses.     

New Eunicellin Diterpenes and 9,10‐Secosteroids from the Gorgonian Muricella sibogae

Bioactivity‐guided isolation of the rare gorgonian Muricella sibogae (Nutting ) yielded the two new eunicellin diterpenes sibogin A and B ( 1 and 2 ), the three new 9,10‐secosteroids sibogol A–C ( 6 – 8 ), together with the three known eunicellin diterpenes 3 – 5 and the five known 9,10‐secosteroids 9 – 13 . Their structures were established by extensive spectral analysis (1D‐ and 2D‐NMR, IR, and MS). The cytotoxicity of the isolates 1 – 13 was evaluated in vitro against the selected tumor cell lines P388 and BEL‐7402. All the compounds showed only weak activity against P388 cell lines, with an inhibition rate ranging from 10 to 60% at a concentration of 50 μg/ml, whereas the were inactive against BEL‐7402 cell lines.     

Three New Terpenoids from Pinus yunnanensis

A new abietatrienoid, 15‐methoxydidehydroabietic acid ( 1 ), a new ring B‐seco abietatrienoid, 10‐hydroxy‐9,10‐secoabieta‐8,11,13‐trien‐18‐oic acid ( 2 ), and a new tetracyclic triterpenoid, pinusyunnanol ( 3 ), together with five known compounds, were obtained from the twigs and needles of Pinus yunnanensis. The structures of the new compounds were elucidated by means of extensive spectroscopic analyses.     

Two New Cytotoxic Nonsulfated Pentasaccharide Holostane (=20‐Hydroxylanostan‐18‐oic Acid γ‐Lactone) Glycosides from the Sea Cucumber Holothuria grisea

Two new lanostane‐type nonsulfated pentasaccharide triterpene glycosides, 17‐dehydroxyholothurinoside A ( 1 ) and griseaside A ( 2 ), were isolated from the sea cucumber Holothuria grisea. Their structures were elucidated by spectroscopic methods, including 2D‐NMR and MS experiments, as well as chemical evidence. Compounds 1 and 2 possess the same pentasaccharide moieties but differ slightly in their side chains of the holostane‐type triterpene aglycone. The structures of the two new glycosides were established as (3β,12α)‐22,25‐epoxy‐3‐{(O‐β‐D ‐glucopyranosyl‐(1→4)‐O‐[O‐3‐O‐methyl‐β‐D ‐glucopyranosyl‐(1→3)‐O‐β‐D ‐glucopyranosyl‐(1→4)‐6‐deoxy‐β‐D ‐glucopyranosyl‐(1→2)]‐β‐D ‐xylopyranosyl)oxy}‐12,20‐dihydroxylanost‐9(11)‐en‐18‐oic acid γ‐lactone ( 1 ) and (3β,12α)‐3‐{(O‐β‐D ‐glucopyranosyl‐(1→4)‐O‐[O‐3‐O‐methyl‐β‐D ‐glucopyranosyl‐(1→3)‐O‐β‐D ‐glucopyranosyl‐(1→4)‐6‐deoxy‐β‐D ‐glucopyranosyl‐(1→2)]‐β‐D ‐xylopyranosyl)oxy}‐12,20,22‐trihydroxylanost‐9(11)‐en‐18‐oic acid γ‐lactone ( 2 ). The 17‐dehydroxyholothurinoside A ( 1 ) and griseaside A ( 2 ) exhibited significant cytotoxicity against HL‐60, BEL‐7402, Molt‐4, and A‐549 cancer cell lines.     

Three New Lignan Derivatives from Lindera glauca (Siebold et Zucc.) Blume

Two new aryl‐tetralin lignan glycosides, linderanosides A and B ( 1 and 2 , resp.), and a new dihydrobenzofuran neolignan glycoside, linderanoside C ( 3 ), together with five known lignan derivatives ( 4 – 8 ) were isolated from the trunk of Lindera glauca. The structures of these new compounds were determined through spectroscopic analyses, including extensive 2D‐NMR data and acid hydrolysis. The absolute configurations of the compounds were clarified by circular dichroism (CD) spectroscopic studies. Compounds 1 – 8 were evaluated for their cytotoxicity against A549 (non‐small cell lung adenocarcinoma), SK‐OV‐3 (ovarian cancer cells), A498 (human kidney epithelial cells), and HCT‐15 (colon cancer cells) human tumor cell lines using sulforhodamine B assays in vitro.     

Huangqiyenins G – J,Four New 9,10‐Secocycloartane (=9,19‐Cyclo‐9,10‐secolanostane) Triterpenoidal Saponins from Astragalus membranaceus Bunge Leaves

Four new 9,10‐secocycloartane (=9,19‐cyclo‐9,10‐secolanostane) triterpenoidal saponins, named huangqiyenins G–J ( 1 – 4 , resp.), were isolated from Astragalus membranaceus Bunge leaves. The acid hydrolysis of 1 – 4 with 1M aqueous HCl yielded D ‐glucose, which was identified by GC analysis after treatment with L ‐cysteine methyl ester hydrochloride. The structures of 1 – 4 were established by detailed spectroscopic analysis as (3β,6α,10α,16β,24E)‐3,6‐bis(acetyloxy)‐10,16‐dihydroxy‐12‐oxo‐9,19‐cyclo‐9,10‐secolanosta‐9(11),24‐dien‐26‐yl β‐D ‐glucopyranoside ( 1 ), (3β,6a,10α,24E)‐3,6‐bis(acetyloxy)‐10‐hydroxy‐12,16‐dioxo‐9,19‐cyclo‐9,10‐secolanosta‐9(11),24‐dien‐26‐yl β‐D ‐glucopyranoside ( 2 ), (3β,6α,9α,10α,16β,24E)‐3,6‐bis(acetyloxy)‐9,10,16‐trihydroxy‐9,19‐cyclo‐9,10‐secolanosta‐11,24‐dien‐26‐yl β‐D ‐glucopyranoside ( 3 ), and (3β,6α,10α,24E)‐3,6‐bis(acetyloxy)‐10‐hydroxy‐16‐oxo‐9,19‐cyclo‐9,10‐secolanosta‐9(11),24‐dien‐26‐yl β‐D ‐glucopyranoside ( 4 ).     

New Polyoxygenated Triterpenoids from Stachyurus himalaicus var. himalaicus

Two new polyoxygenated triterpenoids, stachlic acid A (= (2α,3β)‐2,3,23,29‐tetrahydroxyolean‐12‐en‐28‐oic acid; 1 ) and stachlic acid B (= (2α,3α)‐2,29‐dihydroxy‐3,23‐[(1,1‐dimethylmethylene)dioxy]olean‐12‐ene‐28‐oic acid; 2 ), were isolated from Stachyurus himalaicus var. himalaicus. Their structures were established by means of extensive spectroscopic studies and chemical evidence. The purified product 1 was found to have moderate in vitro cytotoxic activity against human Hela cells.     

Scyphiphorins A and B,Two New Iridoid Glycosides from the Stem Bark of a Chinese Mangrove Scyphiphora hydrophyllacea

Two new iridoid glycosides, named scyphiphorins A ( 1 ) and B ( 2 ), together with four known compounds, geniposidic acid (=(1S,4aS,7aS)‐1‐(β‐D ‐glucopyranosyloxy)‐1,4a,5,7a‐tetrahydro‐7‐(hydroxymethyl)cyclopenta[c]pyran‐4‐carboxylic acid; 3 ), 4‐(4‐hydroxy‐3‐methoxybenzyl)butan‐2‐one, oleanolic acid (=(3β)‐3‐hydroxyolean‐12‐en‐28‐oic acid), and stigmasterol β‐D ‐glucoside (=(3β,22E)‐stigmasta‐5,22‐dien‐3‐yl β‐D ‐glucopyranoside), were isolated for the first time from the stem bark of a Chinese mangrove, Scyphiphora hydrophyllacea Gaertn . f. The structures of compounds 1 and 2 were determined as 10‐O‐benzoylgeniposidic acid and 10‐O‐[(2E,6R)‐8‐hydroxy‐2,6‐dimethyl‐1‐oxooct‐2‐en‐1‐yl]geniposidic acid, respectively, on the basis of spectroscopic data and chemical methods, including 2D NMR techniques.     

Two Novel Abietane Diterpenoids from Illicium wardii A.C.Sm.

Two novel abietane diterpenoids, wardinols A and B ( 1 and 2 , resp.), together with five known diterpenoids, 3 – 7 , were isolated from the fruits of Illicium wardii A.C.Sm . Their structures were elucidated on the basis of intensive spectroscopic analysis, including 1D‐ and 2D‐NMR spectroscopy. Wardinol A ( 1 ) is a rare 9,10‐epoxy‐9,10‐secoabietane diterpenoid. All of the isolated compounds were evaluated for their cytotoxicities against three human tumor cell lines, A549, HCT116, and CCRF‐CEM.     

New Steroids and a New Alkaloid from the Gorgonian Isis minorbrachyblasta: Structures,Cytotoxicity, and Antilarval Activity

Two new polyoxygenated steroids, (1α,3β,7α,11α,12β)‐gorgost‐5‐ene‐1,3,7,11,12‐pentol 12‐acetate ( 1 ) and 11‐O‐acetyl‐22‐epihippuristanol ( 2 ), and a new alkaloid, 2,3,5,6,11,11b‐hexahydro‐2‐hydroxy‐1H‐indolizino[8,7‐b]indole‐2‐carboxylic acid ( 3 ), together with three known compounds, 22‐epihippuristanol ( 4 ), hippuristanol ( 5 ), and tryptamine ( 6 ), were isolated from the EtOH/CH₂Cl₂ extracts of the South China Sea gorgonian Isis minorbrachyblasta. The structures of the new compounds were determined by spectroscopic methods. Compound 1 showed weak cytotoxicity against A549, HONE1, and HeLa cancer cell lines and strong antilarval activity towards Bugula neritina larvae with an EC₅₀ value of 5.8 μg/ml. Compound 5 showed moderate cytotoxicity against A549, HONE1, and HeLa cell lines, and the epimer mixture 4 / 5 (weight ratio 3 : 2) exhibited potent cytotoxicity against A549 and HONE1 cell lines with IC₅₀ values of 4.2 and 4.8 μg/ml, which indicated that epimers 4 and 5 might have a synergistic effect on their cytotoxicity against A549 and HONE1 cell lines.     

Two New 7‐Dehydrobrefeldin A Acids from Cylindrocarpon obtusisporum,an Endophytic Fungus of Trewia nudiflora

Two new 7‐dehydrobrefeldin A acids, (2E,4R*)‐4‐hydroxy‐4‐{(1R*,2S*)‐4‐oxo‐2‐[(1E)‐6‐oxohept‐1‐en‐1‐yl]cyclopentyl}but‐2‐enoic acid ( 3 ) and (2E,4R*)‐4‐hydroxy‐4‐{(1R*,2S*)‐2‐[(1E,6S*)‐6‐hydroxyhept‐1‐en‐1‐yl]‐4‐oxocyclopentyl}but‐2‐enoic acid ( 4 ), were isolated from the endophytic fungal strain Cylindrocarpon obtusisporum (Cooke & Harkness ) Wollenw . of Trewia nudiflora, together with two known compounds, 7‐dehydrobrefeldin A ( 2 ) and brefeldin A ( 1 ). Their structures were determined on the basis of extensive 1D‐ and 2D‐NMR‐spectral analysis.     

Unusual Guaiane Sesquiterpenoids from Artemisia rupestris

Two new guaiane sesquiterpenoids, (1β,5β)‐1‐hydroxyguaia‐4(15),11(13)‐dieno‐12,5‐lactone ( 1 ) and 1,5‐epoxy‐4‐hydroxyguai‐11(13)‐en‐12‐oic acid ( 2 ), together with five known compounds, rupestonic acid ( 3 ), strobilactone A ( 4 ), antiquorin ( 5 ), isosclerone ( 6 ), and 5‐hydroxy‐2′,3′,4′,7,8‐pentamethoxyflavone ( 7 ), were isolated from a 95% EtOH extract of Artemisia rupestris. Compounds 1 and 2 are rare examples of guaiane sesquiterpenoids, incorporating a 12,5‐lactone group or featuring a 1,5‐epoxy ring, respectively. The structures of 1 and 2 were identified by various spectroscopic methods. Compounds 1, 4 , and 5 exhibited moderate cytotoxic activities against the human lung cancer 95‐D cell line with IC₅₀ values of 11.3, 19.8, and 34.5 μM , respectively.     

Paecilomycines A and B,Novel Diterpenoids,Isolated from Insect‐Pathogenic Fungi Paecilomyces sp. ACCC 37762

Two new diterpenoids, named paecilomycine A ( 1 ) and paecilomycine B ( 2 ), including a novel skeleton with a five‐membered lactone ring, together with three known labdane diterpenoids, rel‐(1R,3S,4aS,5R,8aS)‐5‐[(3E)‐4‐carboxy‐3‐methylbut‐3‐en‐1‐yl]decahydro‐3‐hydroxy‐1,4a‐dimethyl‐6‐methylidenenaphthalene‐1‐carboxylic acid ( 3 ), botryosphaerin E ( 4 ), and agathic acid ( 5 ), were isolated from solid culture of the insect pathogenic fungi strain Paecilomyces sp. The structures of all compounds were established on the basis of comprehensive spectroscopic studies. The relative configurations of 1 and 2 were determined by single‐crystal X‐ray diffraction analyses.     

Seco‐Tremulanes from Cultures of the Basidiomycete Flavodon flavus BCC 17421

A new seco‐tremulane, 11,12‐epoxy‐5,6‐secotremula‐1,6(13)‐dien‐5,12‐olide ( 1 ), was isolated together with the known compounds, conocenolides A ( 2 ) and B ( 3 ), tremulenediol A ( 4 ), tremulenolide A ( 5 ), and two lanostane triterpenoids, trametenolic acid B ( 6 ), and pinicolic acid A ( 7 ), from cultures of the basidiomycete Flavodon flavus BCC 17421. Interconversion of conocenolides A/B was demonstrated. Compound 1 exhibited weak cytotoxic activities, whereas tremulenediol A showed antiplasmodial activity (IC₅₀ 8.6 μg/ml). Pinicolic acid A exhibited activity against herpes simplex virus type‐1 (IC₅₀ 15 μg/ml) as well as cytotoxic activities.     

Coordination of Ligands That Contain Thiocarbonyl,Carbonyl, or Thiolate Functionalities to Complex Fragments of Palladium in Various Oxidation States

Two phosphine ligands of [Pd(PPh₃)₄] were substituted by π(C?S) coordination of 4‐bromodithiobenzoic acid methyl ester resulting in complex 1 . The same ester, after alkylation, afforded the dicationic complex bis(μ‐methanethiolato)tetrakis(triphenylphosphine)dipalladium(2+) bis(tetrafluoroborate) ( 2 ) from the same palladium source. A related thiolato‐bridged complex, bis(μ‐methanethiolato)bis(1‐methylpyridin‐2(1H)‐ylidene)bis(triphenylphosphine)dipalladium(2+) bis(tetrafluoroborate) ( 4 ) and the trinuclear cluster tris(μ‐methanethiolato)tris(triphenylphosphine)tripalladium(+)(3Pd? Pd) ( 5 ) resulted from treatment of a known cationic pyridinylidene complex with MeSLi. The double oxidative substitution reaction of [Pd(PPh₃)₄] with 1,5‐dichloro‐9,10‐anthraquinone afforded trans‐dichloro[μ‐(9,10‐dihydro‐9,10‐dioxoanthracene‐1,5‐diyl)]tetrakis(triphenylphosphine)dipalladium ( 6 ). Some of these complexes could be fully characterized by ¹H‐, ¹³C‐, and ³¹P‐NMR spectroscopy, mass spectrometry, and elemental analysis. The crystal and molecular structures of all of them, and of trans‐bis(1,3‐dihydro‐1,3‐dimethyl‐2H‐imidazol‐2‐ylidene)diiodopalladium ( 3 ), were determined by single‐crystal X‐ray diffraction.     

Two New Eremophilane‐Type Sesquiterpenoids from the Rhizomes of Ligularia veitchiana (Hemsl.) Greenm

Two new eremophilane‐type sesquiterpenoids eremophil‐6‐en‐11‐ol ( 1 ) and (7α,9α,10α)‐9,10‐epoxy‐eremophilan‐11‐ol ( 2 ), together with a known eremophilane‐type (6α,8α)‐6,8‐dihydroxyeremophil‐7(11)‐en‐12‐oic acid 12,8‐lactone ( 3 ) were isolated from the rhizomes of Ligularia veitchiana. The structures of 1 and 2 were established by spectral analysis including ¹H‐ and ¹³C‐NMR, HSQC, HMBC, and HR‐ESI‐MS data. The compounds 1 and 3 were assessed against lung‐cancer (A549) and stomach‐cancer (BCG823) cell lines by the MTT method. The results showed that 1 exhibited significant inhibiting activities on the growth of these cancer cells with IC₅₀ values between 1–100 μg/ml, whereas compound 3 had no effect on the same cell lines.