A Guaianolide Sesquiterpene,a Chromenone,and a Flavanone from Ligularia macrophylla

Three new compounds, (5β,9β)‐guaia‐6,10(14)‐dien‐9‐ol (=rel‐(1R,3aS,5R,8aR)‐1,2,3,3a,4,5,6,8a‐octahydro‐1‐methyl‐4‐methylene‐7‐(1‐methylethyl)azulen‐5‐ol; 1 ), 6‐acetyl‐8‐methoxy‐2,3‐dimethylchromen‐4‐one (=6‐acetyl‐8‐methoxy‐2,3‐dimethyl‐4H‐1‐benzopyran‐4‐one; 2 ), and (2S)‐3′‐hydroxy‐5′,7‐dimethoxyflavanone (=(2S)‐2,3‐dihydro‐2‐(3‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one; 3 ) were isolated from the roots and rhizomes of Ligularia macrophylla, together with seven known compounds. Their structures and configurations were elucidated by spectroscopic methods, including 2D‐NMR techniques.     

Terpenoids from Croton regelianus

Two new terpenoids, the bisnorditerpene rel‐(5β,8α,10α)‐8‐hydroxy‐13‐methylpodocarpa‐9(11),13‐diene‐3,12‐dione ( 1 ) and the guaiane sesquiterpene rel‐(1R,4S,6R,7S,8aR)‐decahydro‐1‐(hydroxymethyl)‐4,9,9‐trimethyl‐4,7‐(epoxymethano)azulen‐6‐ol ( 2 ), together with seven known compounds, were isolated from Croton regelianus var. matosii. The structures of the isolated compounds were determined by HR‐ESI‐TOF and a combination of 1D‐ and 2D‐NMR experiments.     

New Lignan,Benzofuran, and Sesquiterpene Derivatives from the Roots of Leontopodium alpinum and L. leontopodioides

Three new compounds, including a benzofuran, 1‐{(2R*,3S*)‐3‐(β‐D ‐glucopyranosyloxy)‐2,3‐dihydro‐2‐[1‐(hydroxymethyl)vinyl]‐1‐benzofuran‐5‐yl}ethanone ( 1 ), a lignan, [(2S,3R,4R)‐4‐(3,4‐dimethoxybenzyl)‐2‐(3,4‐dimethoxyphenyl)tetrahydrofuran‐3‐yl]methyl (2E)‐2‐methylbut‐2‐enoate ( 2 ), and a silphiperfolene‐type sesquiterpene, [(1S,2Z,3aS,5aS,6R,8aR)‐1,3a,4,5,5a,6,7,8‐octahydro‐1,3a,6‐trimethylcyclopenta[c]pentalen‐2‐yl]methyl acetate ( 3 ), together with the known coumarins obliquin ( 4 ) and its 5‐methoxy derivative 5 were isolated from the roots of Leontopodium alpinum. Another known coumarin derivative, 5‐hydroxyobliquin ( 6 ), was isolated from the roots of L. leontopodioides. The structures of these compounds were established by spectroscopic studies.     

Biflavones and Furanone Glucosides from Zabelia tyaihyonii

Two new biflavones, (aR)‐3′‐methoxycupressuflavone ( 1 ) and (aR)‐3′,3′′′‐dimethoxycupressuflavone ( 2 ), and two new furanone glucosides, zabeliosides A and B ( 3 and 4 , resp.), along with two known biflavones, cupressuflavone ( 5 ) and amentoflavone ( 6 ), were isolated from the leaves of Zabelia tyaihyonii. The structures of the new compounds were elucidated by 1D‐ and 2D‐NMR, HR‐ESI‐MS, and circular dichroism.     

Phenolic Metabolites from the Stems and Leaves of Sophora flavescens

Two new compounds, (?)‐(6aR,11aR)‐4‐methoxy‐8,9‐(methylenedioxy)pterocarpan 3‐O‐β‐D ‐glucopyranoside ( 1 ) and 5‐hydroxy‐7‐methoxyisoflavone 4′‐O‐β‐D ‐xylopyranosyl‐(1→6)‐β‐D ‐glucopyranoside ( 2 ), were isolated, together with 30 known compounds from the stems and leaves of Sophora flavescens Aition . Their structures were elucidated by extensive spectroscopic analysis, including HR‐ESI‐MS data. A preliminary comparison of phenolic metabolite profiles, based on the qualitative HPLC analysis, indicated that the composition of the roots and the aerial parts were significantly different.     

New Sesquiterpenoids from Salvia castanea Diels f. tomentosa

Two new sesquiterpenoids, castanin A (= 4R*,5R*,5aS*,8S*,8aR*,8bR*)‐8‐formyl‐4,5,5a,6,7,8,8a,8b‐octahydro‐5,8b‐dihydroxy‐3,5a,8‐trimethyl‐2‐oxo‐2H‐indeno[4,5‐b]furan‐4‐yl acetate; 1 ) and castanin B (= 1aS*,6R*,6aS*,7aR*,9aR*)‐1a,2,6,6a,7a,8,9,9a‐octahydro‐1a,5,7a‐trimethylbisoxireno[4,5 : 8,9]cyclodeca[1,2‐b]furan‐6‐yl acetate; 2 ) were isolated from the aerial parts of Salvia castanea Diels f. tomentosa, together with two known compounds, oplophanone and 1β,6α‐dihydroxyeudesm‐4(14)‐ene. Their structures were elucidated by spectroscopic analyses and, in the case of 2 , also by X‐ray crystallography. Castanin A ( 1 ) represents a novel sesquiterpenoid, with a contracted ring A, derived from eudesmanolide. A possible biogenetic pathway is proposed.     

Rubriflorin A and B,Two Novel Partially Saturated Dibenzocyclooctene Lignans from Schisandra rubriflora

From the stems of Schisandra rubriflora, two novel partially saturated dibenzocyclooctene lignans, named rubriflorin A ( 1 ) and B ( 6 ), as well as the seven known partially saturated dibenzocyclooctene lignans kadsumarin A ( 2 ), kadsurin ( 3 ), heteroclitin B ( 4 ), heteroclitin C ( 5 ), heteroclitin D ( 7 ), interiorin ( 8 ), and interiorin B ( 9 ) were isolated. The structures of the new compounds 1 and 6 were established on the basis of spectral analysis as (5R,6S,7R,8R,13aS)‐8‐(acetyloxy)‐5,6,7,8‐tetrahydro‐1,2,3,13‐tetramethoxy‐6,7‐dimethylbenz([3,4]cycloocta[1,2‐f][1,3]benzodioxol‐5‐yl (2Z)‐2‐methylbut‐2‐enoate and (6R,7R,12aS)‐7,8‐dihydro‐12‐hydroxy‐1,2,3,10,11‐pentamethoxy‐6,7‐dimethyl‐6H‐dibenzo[a,c]cycloocten‐5‐one, respectively.     

Neoclerodane Diterpenes from Amoora stellato‐squamosa

From the twigs of Amoora stellato‐squamosa, five new neoclerodane diterpenes have been isolated and characterized, methyl (13E)‐2‐oxoneocleroda‐3,13‐dien‐15‐oate (=methyl (2E)‐3‐methyl‐5‐[(1S,2R,4aR,8aR)‐1,2,3,4,4a,7,8,8a‐octahydro‐1,2,4a,5‐tetramethyl‐7‐oxo‐naphthalen‐1‐yl]pent‐2‐enoate; 1 ), (13E)‐2‐oxoneocleroda‐3,13‐dien‐15‐ol (=(4aR,7R,8S,8aR)‐1,2,4a,5,6,7,8,8a‐octahydro‐8‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐4,4a,7,8‐tetramethylnaphthalen‐2(1H)‐one; 2 ), (3α,4β,13E)‐neoclerod‐13‐ene‐3,4,15‐triol (=(1R,2R,4aR, 5S,6R,8aR)‐decahydro‐5‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalene‐1,2‐diol; 3 ), (3α,4β,13E)‐4‐ethoxyneoclerod‐13‐ene‐3,15‐diol (=(1R,2R,4aR,5S,6R,8aR)‐1‐ethoxydecahydro‐5‐[(E)‐5‐hydroxy‐3‐methylpent‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalen‐2‐ol; 4 ), and (3α,4β,14RS)‐neoclerod‐13(16)‐ ene‐3,4,14,15‐tetrol (=(1R,2R,4aR,5S,6R,8aR)‐decahydro‐5‐[3‐(1,2‐dihydroxyethyl)but‐3‐enyl]‐1,5,6,8a‐tetramethylnaphthalene‐1,2‐diol; 5 ), together with two known compounds, (13E)‐neocleroda‐3,13‐diene‐15,18‐diol ( 6 ) and (13S)‐2‐oxoneocleroda‐3,14‐dien‐13‐ol ( 7 ).     

Unexpected Novel Pheophytin Peroxides from the Leaves of Biden pilosa

Two new pheophytins, bidenphytins A ( 1 ) and B ( 2 ), with peroxide functionalities on ring E, were isolated from Biden pilosa Linn . var. radiata Sch . Bip ., a popular Taiwanese folk medicine. Also isolated were the following six known compounds: pheophytin a ( 3 ), (13²R)‐13²‐hydroxypheophytin a ( 4 ), (13²S)‐13²‐hydroxypheophytin a ( 5 ), (13²R)‐13²‐hydroxypheophytin b ( 6 ), (13²S)‐13²‐hydroxypheophytin b ( 7 ), and aristophyll‐C ( 8 ). Their structures were elucidated by spectroscopic methods (UV, IR, 1D‐ and 2D‐NMR) and by mass spectrometry (HR‐FAB‐MS). Possible biosynthetic pathways for 1 and 2 are proposed.     

Two New Steroidal Saponins from the Processed Polygonatum kingianum

Two new spirostanol saponins, kingianoside I ( 1 ) and kingianoside K ( 2 ), corresponding to (3β,23S,25R)‐23‐hydroxy‐12‐oxospirost‐5‐en‐3‐yl 4‐O‐β‐D ‐glucopyranosyl‐β‐D ‐galactopyranoside ( 1 ) and (3β,25R)‐7‐oxospirost‐5‐en‐3‐yl α‐L ‐arabinofuranosyl‐(1→4)‐[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)]‐β‐D ‐glucopyranoside ( 2 ), along with 13 known compounds, daucosterol, (25R)‐kingianoside G, (25RS)‐kingianoside A, pratioside D₁, (25RS)‐pratioside D₁, (25S)‐kingianoside C, kingianoside C, ginsenoside Rb₁, saponins Tb and Pb, dioscin, gracillin, and saponin Pa, were isolated from the processed rhizomes of Polygonatum kingianum. The structures of the new compounds were elucidated by detailed spectroscopic analyses, including 1D‐ and 2D‐NMR techniques, and chemical methods. Compound 2 contains a novel unusual spirostanol saponin aglycone. Ginsenoside Rb₁ and saponin Tb were isolated for the first time from the genus Polygonatum. The 13 known compounds were detected for the first time in the processed Polygonatum kingianum.     

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.     

Diastereoisomeric ent‐Labdane Diterpenoids from Andrographis paniculata

Four C(8),C(12)‐diastereoisomers, (8S,12S)‐isoandrographolide ( 1 ), (8S,12R)‐isoandrographolide ( 2 ), (8R,12R)‐isoandrographolide ( 3 ), and (8R,12S)‐isoandrographolide ( 4 ) were isolated from the aerial parts of Andrographis paniculata. The structures of the new compounds 1 – 3 were established on the basis of the spectroscopic data including UV, IR, NMR, HR‐ESI‐MS, and X‐ray diffraction analysis.     

Cadinene Derivatives from Eupatorium adenophorum

A new norsesquiterpene named eupatorone (= (4S,4aR,6R)‐1‐acetyl‐6‐(acetyloxy)‐4,4a,5,6‐tetrahydro‐4,7‐dimethylnaphthalen‐2(3H)‐one; 1 ) and a new sesquiterpene derivative named 2‐deoxo‐2‐(acetyloxy)‐9‐oxoageraphorone (= (1R,4S,4aR,6R,8aS)‐6‐(acetyloxy)‐3,4,4a,5,6,8a‐hexahydro‐4,7‐dimethyl‐1‐(1‐methylethyl)naphthalen‐2(1H)‐one; 2 ), together with the five known cadinene derivatives 3 – 7 were isolated from the flower of Eupatorium adenophorum (Spreng. ). Their structures were established by extensive NMR experiments, including 1D and 2D NMR.     

A New Irregular Trihydroxy Sesquiterpene from Teucrium mascatense

A new trihydroxy sesquiterpene, rel‐(1R,4aR,5S,6S,7S,8aR)‐decahydro‐6,8a‐dimethyl‐5‐(propan‐2‐yl)naphthalene‐1,6,7‐triol ( 1 ), has been isolated as a result of the phytochemical investigation on the CH₂Cl₂ extract of Teucrium mascatense. The structure elucidation of the new constituent was carried out by the combined use of 1D‐ (¹H‐ and ¹³C‐NMR) and 2D‐NMR (HMBC and HSQC) spectroscopic analysis, along with mass spectrometric techniques. In addition to the new constituent 1 , the known metabolite 2 , previously isolated from Crataegus pinnatifida, was also identified.     

Terpenoids from the Roots of Ligularia muliensis

Three new eremophilane‐type sesquiterpenes, (6β,8α)‐6‐(acetyloxy)‐8‐hydroxyeremophil‐7(11)‐en‐12,8‐olide ( 1 ), (6α,8α)‐6‐hydroxyeremophil‐7(11)‐en‐12,8‐olide ( 2 ), and (6α,8α)‐6‐(acetyloxy)eremophil‐7(11)‐en‐12,8‐olide ( 3 ) ((8α)‐eremophil‐7(11)‐en‐12,8‐olide = (4aR,5S,8aR,9aS)‐4a,5,6,7,8,8a,9,9a‐octahydro‐3,4a,5‐trimethylnaphtho[2,3‐b]furan‐2(4H)‐one), besides the recently elucidated eremoligularin ( 4 ) and bieremoligularolide ( 5 ), as well as a new highly oxygenated monoterpene, rel‐(1R,2R,3R,4S,5S)‐p‐menthane‐1,2,3,5‐tetrol ( 12 ), together with six known constituents, i.e., the sesquiterpenes 6 and 7 , the norsesquiterpenes 8 – 10 , and the monoterpene 13 , were isolated from the roots of Ligularia muliensis. In addition, an attempt to dimerize 1 to a bieremophilenolide (Scheme) resulted in the generation of the new derivative (6β,8β)‐6‐(acetyloxy)‐8‐chloroeremophil‐7(11)‐en‐12,8‐olide ( 11 ). The new structures were established by means of detailed spectroscopic analysis (IR, FAB‐, EI‐, or HR‐ESI‐MS as well as 1D‐ and 2D‐NMR experiments). Compounds 4 and 5 were evaluated for their antitumor effects in vitro (Table 3).     

Three New Diterpenoids from Rabdosia lophanthoides var. gerardiana

Three new diterpenoids, together with three known ones, were isolated from the air‐dried whole herbs of Rabdosia lophanthoides var. gerardiana. The structures of the new diterpenoids were established as 3,4‐dihydro‐11‐hydroxy‐10‐(1‐hydroxy‐1‐methylethyl)‐2,2,6‐trimethylnaphtho[1,8‐bc]oxocin‐5(2H)‐one ( 1 ), 11,12,15‐trihydroxyabieta‐5,8,11,13‐tetraen‐7‐one ( 2 ), (2R,3S,4S,4aR,8S,9aS,13aS,16aS)‐3,4,4a,8,9,9a,10,11,12,13,14,16a‐dodecahydro‐2‐(hydroxymethyl)‐6,6,10,10‐tetramethyl‐2H‐benzo[4,5]cyclohepta[1,2‐h]pyrano[2,3‐b][1,4]benzodioxepine‐3,4,8,13a,15(6H)‐pentol ( 3 ) by spectroscopic methods, including extensive 1D‐ and 2D‐NMR analyses. The structures of the known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature.     

Iridoids from Viburnum cylindricum

Two new iridoids, methyl (+)‐rel‐(1R,3S,4R,5R,8R,9R)‐1,3,4,5,8,9‐hexahydro‐8‐hydroxy‐3‐methoxy‐2H‐1a,2‐dioxacyclopent[cd]indene‐4‐carboxylate ( 1 ) and methyl (+)‐rel‐(1R,3S,4S,5R,8R,9R)‐1,3,4,5,8,9‐hexahydro‐8‐hydroxy‐3‐methoxy‐2H‐1a,2‐dioxacyclopent[cd]indene‐4‐carboxylate ( 2 ), were isolated from Viburnum cylindricum along with 14 known compounds. Their structures were determined by spectroscopic analyses. This type of iridoids bearing a MeO group at C(3) was discovered for the first time.     

Squadinorlignoside: A Novel 7,9′‐Dinorlignan from the Stems of Annona squamosa

Two new polar lignans, i.e., squadinorlignoside (= 4‐[(1E)‐1‐(hydroxymethyl)‐3‐(4‐hydroxyphenyl)prop‐1‐en‐1‐yl]phenyl β‐D ‐glucopyranoside; 1 ) and (6R,7R,8S)‐7a‐[(β‐D ‐glucopyranosyl)oxy]‐1‐methoxyisolariciresinol ( 2 ) were isolated from the stems of Annona squamosa, together with eight known lignans and five known neolignans (compounds 3 – 15 ; Fig. 1). All of these constituents are reported for the first time from the genus Annona. The structures, absolute configurations, and selected conformational aspects of the new compounds were elucidated spectroscopically. Compound 1 is the first example of a 7,9′‐dinorlignan natural product.     

A New Cembranoid Diterpene and Other Related Metabolites from the South‐China‐Sea Soft Coral Lobophytum crassum

A new hydroperoxy‐substituted cembranoid diterpene, 2‐hydroperoxysarcophine (= (1aR*,4E,11E,14aR*)‐2,3,6,7,10a,13,14,14a‐octahydro‐10a‐hydroperoxy‐1a,5,8,12‐tetramethyloxireno[9,10]cyclotetradeca[1,2‐b]furan‐9(1aH)‐one; 1 ), was isolated from the marine soft coral Lobophytum crassum. Also isolated were two other cembranoid diterpenes, obtained for the first time from a natural source, i.e., 7β,8β‐epoxy‐4α‐hydroxycembra‐1(15),2,11‐trien‐16,2‐olide ( 2 ) and 7β,8β‐epoxy‐4β‐hydroxycembra‐1(15),2,11‐trien‐16,2‐olide ( 3 ), along with three further cembranoid derivatives, five sterols, and two open‐chain metabolites. Their structures and relative configurations were elucidated on the basis of extensive spectroscopic analyses including 1D‐ and 2D‐NMR, and HR‐ESI‐MS experiments.     

Three Terpenoids and a Tocopherol‐Related Compound from Ricinus communis

Four new compounds named (3E,7Z,11E)‐19‐hydroxycasba‐3,7,11‐trien‐5‐one ( 1 ), 6α‐hydroxy‐10β‐methoxy‐7α,8α‐epoxy‐5‐oxocasbane‐20,10‐olide ( 2 ), 15α‐hydroxylup‐20(29)‐en‐3‐one ( 3 ), and (2R,4aR, 8aR)‐3,4,4a,8a‐tetrahydro‐4a‐hydroxy‐2,6,7,8a‐tetramethyl‐2‐(4,8,12‐trimethyltridecyl)‐2H‐chromene‐5,8‐dione ( 4 ) were isolated from the MeOH extracts of the aerial parts of Ricinus communis L. by chromatographic methods. Their structures were elucidated by extensive spectroscopic experiments.