Two New Diterpenoids and other Constituents from Isodon Nervosus

Two new ent‐kaurane diterpenoids, 15β‐hydroxy‐6,7‐seco‐6,11β:6,20‐diepoxy‐1α,7‐olide‐ent‐kaur‐16‐ene ( 1 ), 11α,15α‐dihydroxy‐6β‐methoxy‐6,7‐seco‐6,20‐epoxy‐1α,7‐olide‐ent‐kaur‐16‐ene ( 2 ), together with four known diterpenoids, nodosin ( 3 ), isodocarpin ( 4 ), odonicin ( 5 ) and maoyecrystal F ( 6 ) were isolated from the aerial parts of Isodon nervosus. The structures of the new compounds were elucidated on the basis of their spectral evidence, especially on 2D NMR.     

Eremophilane‐Type Sesquiterpenes from the Roots of Ligularia virgaurea

From the roots of Ligularia virgaurea, five new eremophilane‐type sesquiterpenes were isolated, including three new eremophilenolides, 6β‐(angeloyloxy)‐1α,8β,10β‐trihydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 1 ), 6β‐(angeloyloxy)‐1β,10β‐epoxy‐8β‐ethoxyeremophil‐7(11)‐en‐12,8α‐olide ( 2 ), and 1β,10β‐epoxy‐8β‐ethoxy‐6β‐[(2‐methylacryloyl)oxy]eremophil‐7(11)‐en‐12,8α‐olide ( 3 ), two new noreremophilanes, 3β‐[(2‐methylacryloyl)oxy]‐8‐oxo‐12‐noreremophil‐6‐en‐11‐one ( 9 ), and 9β‐hydroxy‐8‐oxo‐12‐noreremophil‐6‐en‐11‐one ( 10 ), and six known eremophilanes, namely 4 – 8 , and 11 . Their structures were elucidated by means of spectral methods, such as IR, HR‐ESI‐MS, and 1D‐ and 2D‐NMR, and by comparison of the spectral data with those reported for structurally related compounds.     

Sterols from the Stems of Momordica charantia

A new sterol, 5α,6α‐epoxy‐3β‐hydroxy‐(22E,24R)‐ergosta‐8,22‐dien‐7‐one ( 1 ), together with eight known sterols, 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8,22‐diene‐3β,7α‐diol ( 2 ), 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8,22‐diene‐3β,7β‐diol ( 3 ), 5α,6α‐epoxy‐(22E,24R)‐ergosta‐8(14),22‐diene‐3β,7α‐diol ( 4 ), 3β‐hydroxy‐(22E,24R)‐ergosta‐5,8,22‐trien‐7‐one ( 5 ), ergosterol peroxide ( 6 ), clerosterol ( 7 ), decortinol ( 8 ), and decortinone ( 9 ), were isolated from the stems of Momordica charantia. Their structures were elucidated by mean of extensive spectroscopic methods, including ¹H, ¹³C, 2D‐NMR and HR‐EI‐MS, as well as comparison with the literature data. Compounds 1 , 4 , 5 , 8 , and 91 were not cytotoxic against the SK‐Hep 1 cell line.     

New Sesquiterpenes from Ligulariopsis Shichuana

A thorough investigation of Ligulariopsis shichuana afforded five new sesquiterpenes, including 1β,10β‐epoxy‐3α‐angeloyloxy‐9β‐acetoxy‐8α,11β‐dihydroxybakkenolide ( 1 ), 1β,7‐dihydroxy‐3β‐acetoxy‐noreremophil‐6(7),9(10)‐dien‐8‐one ( 2 ), 8α‐hydroxy‐3‐oxoeremophil‐1(2),7(11),9(10)‐trien‐8β(12)‐olide ( 3 ), 1β,10β‐dihydroxy‐3β‐acetoxyeremophil‐7(11),8(9)‐dien‐8(12)‐olide ( 4 ) and 1β,10β‐epoxy‐8,12‐dihydroxy‐3β‐acetoxy‐9β‐angeloyloxyeremophil‐7(11)‐en‐8,12‐disemiketal ( 5 ). Their structures were established by spectroscopic methods and 2D NMR techniques. In addition, bakkenolide ( 1 ) and eremophilenolides ( 5 ) showed antibacterial and cytotoxic activities.     

Sesquiterpenes from Ligularia Fischeri

Phytochemical investigation of the whole plant of Ligularia fischeri afforded two new sesquiterpenes 11‐hydroxy‐eremophil 1(10)‐en‐2,9‐dione (1) ; and 1β,11‐dihydroxy‐eremophil‐9‐ene (2) ; four known compounds (‐)‐4β,7α‐aromadendranediol (3) ; 1β,6α‐dihydroxyeudesm‐4(15)‐ene (4) ; Teucdiol A (5) ; Teucdiol B (6) . The new compound structures were elucidated by spectroscopic methods including 2D‐NMR techniques.     

Sesquiterpenoids and Lactone Derivatives from Ligularia dentata

Seven new compounds were isolated from the roots of Ligularia dentata, including five bisabolane‐type sesquiterpenoids (bisabolane=1‐(1,5‐dimethylhexyl)‐4‐methylcyclohexane), namely (8β,10α)‐8‐(angeloyloxy)‐5,10‐epoxybisabola‐1,3,5,7(14)‐tetraene‐2,4,11‐triol ( 1 ), (8β,10α)‐8‐(angeloyloxy)‐5,10‐epoxythiazolo[5,4‐a]bisabola‐1,3,5,7(14)‐tetraene‐4,11‐diol ( 2 ), (1α,2α,3β,5α,6β)‐1,5,8‐tris(angeloyloxy)‐10,11‐epoxy‐2,3‐dihydroxybisabol‐7(14)‐en‐4‐one ( 3 ), (1α,2α,3β,5α,6β)‐2,5,8‐tris(angeloyloxy)‐10,11‐epoxy‐1,3‐dihydroxybisabol‐7(14)‐en‐4‐one ( 4 ), and (1α,2β,3β,5α,6β)‐1,8‐bis(angeloyloxy)‐2,3‐epoxy‐5,10‐dihydroxy‐11‐methoxybisabol‐7(14)‐en‐4‐one ( 5 ) (angeloyloxy=[(2Z)‐2‐methyl‐1‐oxobut‐2‐enyl]oxy), and two lactone derivatives, (2α,3β,5α)‐2‐(acetyloxy)‐9‐methoxy‐5‐(methoxycarbonyl)‐2,3‐dimethylheptano‐5‐lactone ( 6 ), and (2β,4β)‐2‐ethyl‐5‐hydroxy‐5‐(methoxycarbonyl)‐4,5‐dimethylpentano‐4‐lactone ( 7 ) (α/β denote relative configurations), together with (2E,4R,5S)‐2‐ethylidene‐5‐(methoxycarbonyl)‐4‐methylhexano‐5‐lactone ( 8 ), a known synthetic compound. Compound 2 is the first sesquiterpenoid derivative containing the uncommon benzothiazole moiety. The structures of 1 – 8 were established by spectroscopic methods, especially 2D‐NMR and MS analyses.     

The isomeric compounds nimbolide and isonimbolide

Nimbolide [systematic name: (4α,5α,6α,7α,15β,17α)‐7,15:21,23‐diepoxy‐6‐hydroxy‐4,8‐dimethyl‐1‐oxo‐18,24‐dinor‐11,12‐secochola‐2,13,20,22‐tetraene‐4,11‐dicarboxylic acid γ‐lactone methyl ester], C₂₇H₃₀O₇, was isolated from the leaves of Azadirachta indica, and its isomer, isonimbolide [systematic name: (4α,5α,6α,7α,15α)‐7,15:21,23‐diepoxy‐6‐hydroxy‐4,8‐dimethyl‐1‐oxo‐18,24‐dinor‐11,12‐secochola‐2,16,20,22‐tetra­ene‐4,11‐dicarboxylic acid γ‐lactone methyl ester], was prepared from a novel rearrangement reaction of nimbolide, using boron trifluoride etherate and tetra­butyl­ammonium bromide. The reaction conditions are probably responsible for the ether cleavage, double‐bond rearrangement and reformation of the ether linkage. As a result, there are conformational changes in two cyclo­pentane rings and the side‐chain –CH₂COOMe group. In isonimbolide, an (24) hydrogen‐bond motif is observed.     

Cytotoxic Activity of Capnellene‐8β, 10α‐Diol Derivatives from a Taiwanese Soft Coral Capnella sp.

The sesquiterpene capnellene‐8β, 10α‐diol ( 1 ) was isolated from non‐polar extract of the soft coral Capnella sp. Ten acylation products of capnellene‐8β, 10α‐diol were prepared: 10α‐hydroxy‐8β‐O‐benzoylcapnellene ( 2 ), 10α‐hydroxy‐8β‐O‐p‐toluoylcapnellene ( 3 ), 10α‐hydroxy‐8β‐O‐4‐chlorobenzoyl‐capnellene ( 4 ), 10α‐hydroxy‐8β‐O‐2‐furoylcapnellene ( 5 ), 10α‐hydroxy‐8β‐O‐2‐thiophenoylcapnellene ( 6 ), 10α‐hydroxy‐8β‐O‐4‐fluorobenzoylcapnellene ( 7 ), 10α‐hydroxy‐8β‐O‐4‐propylbenzoylcapnellene ( 8 ), 10α‐hydroxy‐8β‐O‐cinnamoylcapnellene ( 9 ), 10α‐hydroxy‐8β‐O‐4‐nitrobenzoylcapnellene ( 10 ), and 10α‐hydroxy‐8β‐O‐4‐anisoylcapnellene ( 11 ). The structures of capnellene‐8β, 10α‐diol as well as its derivatives were established through standard spectroscopic analysis. The in vitro cytotoxic activities of the eleven compounds were evaluated against Hela, KB, Daoy, and WiDr human tumor cell lines.     

Three Unusual New Sesquiterpenes from Alpinia oxyphylla

Two new norcadinene sesquiterpenes oxyphyllones C and D ( 1 and 2 , resp.), and one new 1,10‐secoguaiane sesquiterpene, (+)‐mandassidion ( 3 ), together with two known compounds, oxyphyllenodiol B ( 4 ) and (1R,2R)‐p‐menth‐3‐ene‐1,2‐diol ( 5 ), were isolated from the fruits of Alpinia oxyphylla. Their structures were determined on the basis of spectroscopic analysis, including 2D‐NMR spectroscopic techniques. Compounds 1, 2 , and 3 exhibited no cytotoxicity against three cancer cell lines.     

Total Synthesis of (+)‐β‐Himachalene

An enantioselective synthesis of (+)‐β‐himachalene ( 2 ) was accomplished starting from (1S,2R)‐1,2‐epoxy‐p‐menth‐8‐ene ( 3 ) in 15 or 16 steps with an overall yield of ca. 6% (Schemes 3, 5, and 6). Key transformations include an Ireland–Claisen rearrangement, a Corey oxidative cyclization, and a ring expansion.     

A new Sequiterpenoid from Eupatorium adenophorum Spreng

A new sequiterpenoid compound 8aα-hydroxy-1-isopropyl-4,7-dimethyl-1,2,3,4,6,8a-hexahydro-naphthalene-2,6-dione(1),together with seven known compounds anti-HH-dimer-coumarin(2),(-)-5-exo-hydroxy-bomeol(3),O-hydroxyl cinnamic acid(4),9β-hydroxy-ageraphorone(5),10Hα-9-oxo-ageraphorone(6),10Hβ-9-oxo-ageraphorone(7)and 9-oxo-10,11-dehydroageraphorone 8,was isolated from the leaves of Eupatorium adenopho-rum Spreng.The structures were elucidated by IR,~1H and ~(13)C NMR,EIMS,HMBC and single-crystal X-ray spec-tral data.     

A Pair of Novel Heptentriol Stereoisomers from the Ascomycete Daldinia concentrica

A pair of novel heptentriol stereoisomers, hept‐6‐ene‐2,4,5‐triols 2 and 3 , were isolated from the culture broth of the ascomycete Daldinia concentrica (Bolton : Fries ) Cesati & De Notaris , besides three known compounds, i.e., 2,3‐dihydro‐5‐hydroxy‐2‐methyl‐4H‐1‐benzopyran‐4‐one ( 1 ), 3,5‐dihydroxy‐2‐(1‐oxobutyl)‐cyclohex‐2‐en‐1‐one ( 4 ), and pyroglutamic acid (=5‐oxo‐L ‐proline; 5 ). Their structures were determined by spectroscopic means, including 2D‐NMR (HMQC, HMBC, ¹H,¹H‐COSY).     

Five New Sesquiterpenoids from Parasenecio petasitoides

From the whole plants of Parasenecio petasitoides, five new sesquiterpenoids were isolated, (E,E)‐3α,9β‐dihydroxy‐6βH,11βH‐13‐norgermacra‐1(10),4‐dien‐11,6‐carbolactone ( 2 ), (E,E)‐2α,9β‐dihydroxy‐6βH,11βH‐13‐norgermacra‐1(10),4‐dien‐11,6‐carbolactone ( 3 ), (E,E)‐2α,9β‐dihydroxy‐6βH,11αH‐13‐norgermacra‐1(10),4‐dien‐11,6‐carbolactone ( 4 ), (E)‐15‐hydroxy‐2‐oxo‐6βH,11αH‐13‐norguaia‐3‐ene‐11,6‐carbolactone ( 7 ), and (E)‐11β,15‐dihydroxy‐2‐oxo‐6βH‐13‐norguaia‐3‐ene‐11,6‐carbolactone ( 8 ), together with three known compounds, deacetyl herbolide A ( 1 ), jacquilenin ( 5 ), and (E)‐15‐hydroxy‐2‐oxo‐6βH,11βH‐13‐norguaia‐3‐ene‐11,6‐carbolactone ( 6 ). The structures of these natural products were elucidated spectroscopically, especially by 1D‐ and 2D‐NMR techniques, in combination with high‐resolution mass spectroscopy.     

Three New Derivatives and Others Constituents from the Roots and Twigs of Trilepisium madagascariense DC

Three new compounds, trilepisflavene ( 1 ), trilepisdepsidone ( 2 ), and daturadiol stearate ( 3 ), together with nine known compounds, 2‐hydroxy‐4‐[(4‐hydroxy‐2‐methoxy‐6‐methylbenzoyl)oxy]‐6‐methylbenzoic acid ( 4 ), lichexanthone ( 5 ), naringenin ( 6 ), 3′,4′,5,7‐tetrahydroxyflavanone ( 7 ), 2‐hydroxybenzoic acid ( 8 ), methyl 2,4‐dihydroxy‐6‐methylbenzoate ( 9 ), β‐amyrin ( 10 ), eurothridiol palmitate ( 11 ), and β‐sitosterol ( 12 ), were isolated from the AcOEt extract of the twigs and the roots of Trilepisium madagascariense. Acetylation of eurothridiol palmitate was carried out and a new acetylated derivative ( 13 ) was obtained. The structures of the isolated and acetylated compounds were elucidated on the basis of spectroscopic analysis. Antimicrobial activity of all these compounds was evaluated using Mueller–Hinton broth (MHB) and Mueller–Hinton agar (MHA) method. Trilepisdepsidone , 2‐hydroxy‐4‐[(4‐hydroxy‐2‐methoxy‐6‐methylbenzoyl)oxy]‐6‐methylbenzoic acid, 3′,4′,5,7‐tetrahydroxyflavanone, and naringenin exhibited moderate to weak antimicrobial activity.     

New Eremophilenolides from Senecio dianthus

From the aerial parts of Senecio dianthus, four new eremophilenolides ( 1 – 4 , resp.) and one new eremophilenolide alkaloid ( 5 ), of the relatively uncommon eremophilenoid‐type sesquiterpenoid lactones, were isolated together with three known sesquiterpenoid lactones, 10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 6 ), 8β,10β‐dihydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 7 ), and 10α‐hydroxy‐1‐oxoeremophila‐7(11),8(9)‐dien‐12,8‐olide ( 8 ). On the basis of IR, MS, and NMR data, particularly 2D‐NMR analyses, the structures of the new compounds were established as: 2β‐(angeloyloxy)‐10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 1 ), 6β‐(angeloyloxy)‐10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 2 ), 2β‐(angeloyloxy)‐8β,10β‐dihydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 3 ), 2β‐(angeloyloxy)‐8α‐hydroxyeremophila‐7(11),9(10)‐dien‐12,8β‐olide ( 4 ), and 8β‐amino‐10β‐hydroxyeremophil‐7(11)‐en‐12,8α‐olide ( 5 ). In addition, the relative configuration of 1 was corroborated by X‐ray diffraction analysis.     

Diterpenoids from Isodon Eriocalyx

Two new diterpenoids, Maoecrystal U and epi‐maoecrystal P , together with nine known diterpenoids and eight other known compounds were isolated from Isodon eriocalyx ( ). The structures of two new diterpenoids were elucidated as 6β‐acetoxy‐15β‐hydroxy‐3α,20‐epoxy‐ent‐kaur‐16‐ene‐1,7‐dione and 16(S)‐methoxymethy‐6β,7β‐dihydroxy‐7α,20‐epoxy‐ent‐kaur‐2,3‐ethenylene‐1,15‐dione on the basis of spectroscopic evidence, especially by 2D NMR techniques.     

Chemical Constituents from the Roots of Patrinia Rupestris

Phytochemical investigation of the roots of Patrinia rupestris afforded a new triterpenoid patrirupin A ( 1 ) and a new iridoid patrirupin B ( 2 ), as well as three known triterpenoids: 3‐oxo‐olean‐12‐en‐28‐oic acid ( 3 ), ursolic acid ( 4 ), α‐amyrin ( 5 ), three known iridoids: isovaltratum ( 6 ), 11‐ethoxyviburtinal ( 7 ), homobaldrinal ( 8 ), five known steroids: ergosterol ( 9 ), ergost‐6,22‐diene‐3β,5α,8α‐triol ( 10 ), 6‐hydroxenone ( 11 ), β‐sitosterol ( 12 ), daucosterol ( 13 ), and two known flavones: 1‐hydroxy‐5‐methoxy xanthen‐9‐one ( 14 ), 3′,4′,5,7‐tetrahydroxyflavanone ( 15 ). The new compounds were characterized by means of spectroscopic methods including UV, IR, 1D, 2D NMR and HRESIMS, and the known ones were established on the basis of comparing their NMR data with those of the corresponding compounds in the literature.     

Structural studies of the chemical constituents of Tithonia tagetiflora Desv. (Asteraceae)

Tithonia tagetiflora Desv. (Asteraceae) is a widespread plant in Vietnam, and the species of Tithonia are known as plants containing many biologically active compounds. However, T. tagetiflora's chemical composition remains mostly unknown. Therefore, we now report the structural elucidation of two new sesquiterpene lactones, 8‐angeloyloxy‐2,14‐epoxygermacra‐4,10(1),11(13)‐trien‐6,12‐olide (1) and 6‐angeloyloxy‐1‐hydroxy‐3,4‐epoxygermacra‐9,11(13)‐dien‐8,12‐olide (2), together with three known compounds, including two norisoprenoids, (6S,9S)‐vomifoliol or (6R,9R)‐vomifoliol (3) and (6S,9S)‐roseoside (4), and one glutinane type triterpene, epi‐glutinol (5), from the leaves of T. tagetiflora. Their structures are established by 1D and 2D NMR spectroscopy, as well as ESI‐MS analysis and comparison with literature data. Copyright © 2013 John Wiley & Sons, Ltd.     

Four Novel Eremophilanolides from Ligularia sagitta

Four new eremophilanolides, isolated from Ligularia sagitta, were identified as (1β,3β,6β,8β,10β)‐6‐acetoxy‐3‐(angeloyloxy)‐1,10‐epoxy‐8‐hydroxyeremophil‐7(11)‐en‐8,12α‐olide ( 1 ), (1β,3β,6β,8β,10β)‐3‐(angeloyloxy)‐1,10‐epoxy‐6,8‐dihydroxyeremophil‐7(11)‐en‐8,12α‐olide ( 2 ), (1β,3β,6β,8β,10β)‐3‐(angeloyloxy)‐1,10‐epoxy‐8‐ethoxy‐6‐hydroxyeremophil‐7(11)‐en‐8,12α‐olide ( 3 ), and (1β,3β,8β,10β)‐3‐(angeloyloxy)‐1,10‐epoxy‐8‐hydroxyeremophil‐7(11)‐en‐8,12α‐olide ( 4 ). Their structures were elucidated by spectroscopic methods, including 2D‐NMR techniques and chemical transformations.     

Hamigerin A and a hamigerin D decomposition product

The sponge Hamigera tarangaensis has yielded eight new compounds and we report here the structure of one of these compounds, hamigeran A, C₂₀H₂₅BrO₅, or methyl 7‐bromo‐4β,6‐di­hydroxy‐1β‐iso­propyl‐3aα,8‐di­methyl‐5‐oxo‐1a,3a,4,5‐tetra­hydro­cyclo­penta­[a]­naphthalene‐4‐carboxyl­ate, and the decomposition product of hamigeran D, C₂₁H₂₈BrNO₄, namely 2‐(8‐bromo‐2β,7‐di­methyl‐4‐oxo‐1,3α‐benzox­aza­n‐5‐yl)‐3‐iso­propylcyclo­pentyl­acetic acid.