A Hydroxylated Lupeol‐Based Triterpenoid Ester Isolated from the Scurrula parasitica Parasitic on Nerium indicum

(3β,7β)‐7‐Hydroxylup‐20(29)‐en‐3‐yl hexadecanoate ( 1 ), a new lupeol‐based triterpenoid ester, along with sixteen known compounds, 7β,15α‐dihydroxylup‐20(29)‐ene‐3β‐O‐palmitate ( 2 ), lupeol palmitate ( 3 ), lupeol ( 4 ), 3‐oxolup‐20(29)‐ene ( 5 ), ursolic acid ( 6 ), cycloeucalenol ( 7 ), stigmasterol ( 8 ), β‐sitosterol ( 9 ), β‐daucosterol ( 10 ), quercetin ( 11 ), quercetin 3‐O‐α‐L ‐arabinoside ( 12 ), quercetin 3‐O‐α‐L ‐rhamnoside ( 13 ), catechin ( 14 ), gitoxigenin 3‐O‐α‐L ‐rhamnoside ( 15 ), gitoxigenin 3‐O‐α‐D ‐glucoside ( 16 ), and digitoxigenin 3‐O‐α‐L ‐rhamnoside ( 17 ), was isolated from the leaves of the Southern China mistletoe, Scurrula parasitica Linn parasitic on Nerium indicum Mill . Their structures were elucidated by spectroscopic analyses, including 2D‐NMR techniques. Cytotoxic activities of compounds 1 – 7 and 11 – 17 were evaluated against three cancer cell lines, PANC‐1, HL‐60, and SGC‐7901, revealing that compounds 4, 6, 11 , and 15 – 17 exhibited effective cytotoxicities, while others were inactive. A structure? activity relationship study of compounds 1 – 5 indicated that the 3‐OH group in lupeol‐based triterpenoids is essential for antitumor activity.     

Bioguided Isolation and Antiproliferative Activity of Constituents from Smilax korthalsii A.D.C. Leaves

Ethyl acetate extract of Smilax korthalsii A.D.C. leaves exhibited antiproliferative activity on leukaemia carcinoma K562, hepatic liver cancer cells WRL and colorectal carcinoma with IC₅₀ of 125.20, 46.10 and 160.00 μM respectively. Isolation of the bioactive ethyl acetate extract of Smilax korthalsii A.D.C. leaves gave eight compounds; 3β‐hydroxyspirost‐5‐ene (diosgenin), 1 , β‐sitosterol, 2 , lup‐5,11,20‐trien‐23‐ol, 3 , uneicos‐9‐enoic acid, 4 , ethylheptadecan‐17‐oic‐9‐enoate, 5 , cis‐octadec‐9‐enoic acid, 6 , hexadec9‐enoic acid, 7 and 11‐methyltridec‐12‐en‐1‐ol, 8 . The isolated compounds were tested against four human cancer cell lines: leukaemia carcinoma, K‐562; hepatic liver cancer cells, WRL; colorectal carcinoma, COLO; and breast carcinoma, MCF‐7 using the MTT assay. Diosgenin 1 exhibited significant antiproliferative activity against all four cell lines (IC₅₀; K562=6.25, WRL=14.34, COLO=38.00, MCF‐7=12.40 μM), while compounds 3, 6 and 7 inhibited the growth of K‐562 at 20, 50 and 100 μM concentrations with IC₅₀ of 90.20, 75.92 and 50.72 μM respectively. Other isolated compounds also showed cytotoxic properties against K‐562, WRL and COLO, but showed low inhibition of MCF‐7.     

Diterpenes from Xylopia langsdorffiana

The phytochemical investigation of Xylopia langsdorffiana A.St.‐Hil. & Tul . led to the isolation of eight diterpenes, i.e., of the four new compounds (5β,7β,8α,9β,10α,12α)‐atisane‐7,16‐diol 7‐acetate ( 1 ), named xylodiol 7‐acetate, (5β,8α,9β,10α,12α)‐16‐hydroxyatisan‐7‐one ( 2 ), named xylopinone, (3α,12Z)‐3‐hydroxy‐ent‐labda‐8(20),12,14‐trien‐18‐oic acid ( 3 ), named labdorffianic acid A, and 8,20‐epoxy‐13‐hydroxy‐ent‐labd‐14‐en‐18‐oic acid ( 4 ), named labdorffianic acid B, and of the four known compounds 5 – 8 , i.e., ent‐kauran‐16‐ol, ent‐kaur‐16‐en‐19‐oic acid, ent‐kaur‐16‐en‐19‐ol, and ent‐trachyloban‐18‐oic acid. The structures were established by IR, HR‐ESI‐MS, and NMR data analysis with the aid of 2D techniques.     

Four New Pregnane Steroids from Aglaia abbreviata and Their Cytotoxic Activities

Four new pregnane steroids, aglaiasterols A–D ( 1 – 4 ), have been isolated from the EtOH extract of stems of Aglaia abbreviata. They were identified as (3α,5α,17Z)‐3‐hydroxypregn‐17‐en‐16‐one ( 1 ), (3β,5α,17E)‐3‐hydroxypregn‐17‐en‐16‐one ( 2 ), (3β,5α,17Z)‐3‐hydroxypregn‐17‐en‐16‐one ( 3 ), and (3α,5α,20S*)‐3‐hydroxy‐16‐oxopregnan‐20‐yl acetate ( 4 ) on the basis of spectroscopic methods, including 1D‐ and 2D‐NMR techniques. Compounds 1 – 4 were evaluated for their cytotoxic activities against K562 (human leukemia), MCF‐7 (human breast cancer), and KB (human oral epithelium cancer) cells, and drug‐resistant cells of K562/A02, MCF‐7/ADM, and KB/VCR. These isolates showed weak to moderate inhibitory effects on the growth of the tested cell lines.     

Three New, 1‐Oxygenated ent‐8,9‐Secokaurane Diterpenes from Croton kongensis

Three new ent‐8,9‐secokaurane diterpenes, kongensins A–C ( 1 – 3 ), were isolated from the aerial parts of Croton kongensis, together with two known compounds, rabdoumbrosanin ( 4 ) and (7α,14β)‐7,14‐dihydroxy‐ent‐kaur‐16‐en‐15‐one ( 5 ). The structures of the new compounds were elucidated by HR‐MS as well as in‐depth 1D‐ and 2D‐NMR analyses. Compounds 1 – 3 showed an unusual oxygenation pattern, with an AcO or OH group at C(1), in combination with a Δ⁸⁽¹⁴⁾ unsaturation ( 1 ) or an 8,14‐epoxide function ( 2, 3 ).     

Chemical Constituents from Alafia Barteri Oliv. Leaves with Cytotoxic Activity

Methanol extract of Alafia barteri leaves showed cytotoxic activity on leukaemia carcinoma K562, and hepatic liver cancer cells WRL (IC₅₀ values 193.1 and 225.0 μM respectively). Isolation of the extract gave ursane triterpenoid, 28‐acety‐urs‐5,20‐dien‐2β,3β,24α‐triol, 1 , together with undecanol, 2 , stigmasterol, 3 and octadecanoic acid, 4 . The structures of these compounds were identified by spectroscopic analysis, including MS, 1D and 2D NMR, and supported with literature data. Compound 1 exhibited cytotoxic activity against K‐562 at 50 and 100 μM concentrations with IC₅₀ 74.22 μM, while compounds 2 , 3 and 4 showed low inhibition of WRL, MCF‐7 and COLO cell lines.     

New ent‐Pimarane Diterpenes from the Roots of Aralia dumetorum

Four new ent‐pimarane diterpenes were isolated from the EtOH extract of Aralia dumetorum, together with three known compounds involving ent‐pimar‐8(14),15‐dien‐19‐oic acid ( 5 ), ent‐pimar‐8(14),15‐dien‐19‐ol ( 6 ), and ent‐kaur‐16‐en‐19‐oic acid ( 7 ). By detailed analyses of the MS, IR, and NMR data, the structures of four new diterpenes were characterized as (5β,9β,10α,13α)‐pimara‐6,8(14),15‐trien‐18‐oic acid ( 1 ), (5β,7β,9β,10α,13α)‐7‐methoxypimara‐8(14),15‐dien‐18‐oic acid ( 2 ), (5β,9β,10α,13α,14β)‐14‐methoxypimara‐7,15‐dien‐18‐oic acid ( 3 ), and (5β,10α,13α,14α)‐14‐hydroxypimara‐7,9(11),15‐trien‐18‐oic acid ( 4 ). The cytotoxic activities of compounds 1  –  7 were assayed in vitro through MTT method.     

ent‐Kaurane Diterpenoids from Isodon phyllostachys

Phytochemical investigation of the medicinal plant Isodon phyllostachys led to the isolation of four new ent‐kaurane diterpenoids, phyllostacins F–I ( 1 – 4 , resp.), together with 11 known compounds, rosthorin A ( 5 ), rabdoternin C ( 6 ), enmenol ( 7 ), oridonin ( 8 ), lasiocarpanin ( 9 ), xerophilusin B ( 10 ), ponicidin ( 11 ), macrocalin B ( 12 ), phyllostachysin A ( 13 ), sculponeatin C ( 14 ), and macrocalyxoformin E ( 15 ). The structures of the new compounds were established by spectroscopic methods, including extensive 1D‐ and 2D‐NMR analyses. Compounds 1, 2, 7, 10 , and 13 were evaluated for their inhibitory activity against K562 and HepG2 cell lines.     

New Sterol Derivatives from the Marine Sponge Xestospongia sp.

Chemical examination of a marine sponge Xestospongia sp. resulted in the isolation of 20 sterol derivatives ( 1 – 20 ), including eight new sterols namely aragusterols J – L ( 1 – 3 ), (5α,7α,12β,22E)‐7,12,18‐trihydroxystigmast‐22‐en‐3‐one ( 4 ), (5α,7α,12β,24R)‐ and (5α,7α,12β,24S)‐7,12,20‐trihydroxystigmastan‐3‐one ( 5 / 6 ), and (5α,7α,12β,22E,24R)‐ and (5α,7α,12β,22E,24S)‐7,12,20‐trihydroxyergost‐22‐en‐3‐one ( 7 / 8 ). The structures of new compounds were determined through extensive spectroscopic analyses and chemical conversion. The sterol diversity was mainly characterized by the presence of a cyclopropane unit at side chain, while compound 4 with 18‐hydroxymethyl group was found in stigmasterol family for the first time. Cytotoxic test revealed the inhibitory effects of compounds 1 , 4 , and 17 against human leukemia cell line K562 with IC₅₀ values of 18.3, 24.1, and 34.3 μm , respectively.     

Polyketides and Meroterpenoids from Neosartorya glabra

Two new polyketides, neosarphenols A and B ( 1 and 2 , resp.), were isolated from Neosartorya glabra, together with six known polyketides, 3 – 8 , and two meroterpenoids, 9 and 10 . The structures of the new compounds were elucidated by comprehensive spectroscopic analysis, especially by HR‐ESI‐MS and NMR experiments. All compounds were evaluated for their cytotoxic activities against MDA‐MB‐231, MCF‐7, and PANC‐1 tumor cell lines; 1 and 6 exhibited selective and moderate cytotoxicities against PANC‐1 cell line.     

Additional Minor Phytoecdysteroids of Serratula wolffii

Three new and one known ecdysteroids were identified in the MeOH extract of the roots of Serratula wolffii. The new compounds isolated were (11α)‐11‐hydroxyshidasterone ( 1 ), (2β,3α,5β,14β,22R)‐2,3,20,22,25‐pentahydroxycholest‐7‐en‐6‐one ( 2 ), and (2β,3α,5β,22R)‐2,3,20,22,25‐pentahydroxycholest‐7‐en‐6‐one ( 3 ), together with the known ponasterone A ( 4 ). This latter compound was now better characterized than earlier. The structures of compounds 1 – 4 were established by extensive spectroscopic techniques, including one‐ and two‐dimensional NMR methods.     

Terpenoids from Two Dicranopteris Species

Two new compounds, (6S,13S)‐6‐{[β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}cleroda‐3,14‐dien‐13‐ol ( 1 ) and kadsuric acid 3‐methyl ester ( 2 ), together with nine known compounds, (6S,13E)‐6‐{[β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}cleroda‐3,13‐dien‐15‐ol ( 3 ), (6S,13S)‐6‐[6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}‐13‐{[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐fucopyranosyl]oxy}cleroda‐3,14‐diene ( 4 ), (6S,13S)‐6‐{[6‐O‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}‐13‐{[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐fucopyranosyl]oxy}cleroda‐3,14‐diene ( 5 ), 15‐hydroxydehydroabietic acid ( 6 ), 15‐hydroxylabd‐8(17)‐en‐19‐oic acid ( 7 ), junicedric acid ( 8 ), (4β)‐kaur‐16‐en‐18‐oic acid ( 9 ), (4β)‐16‐hydroxykauran‐18‐oic acid ( 10 ), and (4β,16β)‐16‐hydroxykauran‐18‐oic acid ( 11 ) were isolated from the fronds of Dicranopteris linearis or D. ampla. Their structures were established by extensive 1D‐ and 2D‐NMR spectroscopy. Compounds 1 and 3 – 8 showed no anti‐HIV activities.     

Uncommon Sesquiterpenoids and New Triterpenoids from Jatropha neopauciflora (Euphorbiaceae)

Eight new terpenoids ( 1 – 8 ) were isolated from the bark of Jatropha neopauciflora, together with eight known compounds. The new isolates include the sesquiterpenoids (1R,2R)‐diacetoxycycloax‐4(15)‐ene ( 1 ); (1R,2R)‐dihydroxycycloax‐4(15)‐ene ( 2 ), (2R)‐δ‐cadin‐4‐ene‐2,10‐diol ( 3 ), (2R)‐δ‐cadina‐4,9‐dien‐2‐ol ( 4 ), (1R,2R)‐dihydroxyisodauc‐4‐en‐14‐ol ( 5 ) and its acetonide 6 (artifact), as well as the two triterpenoids (3β,16β)‐16‐hydroxylup‐20(29)‐en‐3‐yl (E)‐3‐(4‐hydroxyphenyl)prop‐2‐enoate ( 7 ) and (3β,16β)‐16‐hydroxyolean‐18‐en‐3‐yl (E)‐3‐(4‐hydroxyphenyl)prop‐2‐enoate ( 8 ). The structures of these compounds were established by extensive 1D‐ and 2D‐NMR spectroscopic methods, and their absolute configurations were determined by circular‐dichroism (CD) experiments, and by X‐ray crystallographic analysis (compound 7 ; Fig. 3). A plausible biosynthesis of the sesquiterpenoids 1 – 5 is proposed (Scheme), starting from (?)‐germacrene D as the common biogenetic precursor.     

Triterpenoid Saponins from the Spikes of Prunella vulgaris

Three new oleanane‐skeleton triterpenoid saponins, 3β,4β,16α‐17‐carboxy‐16,24‐dihydroxy‐28‐norolean‐12‐en‐3‐yl 4‐O‐β‐D ‐xylopyranosyl‐β‐D ‐glucopyranosiduronic acid ( 1 ), (3β,4β,16α)‐17‐carboxy‐16,24‐dihydroxy‐28‐norolean‐12‐en‐3‐yl β‐D ‐glucopyranosiduronic acid methyl ester ( 2 ), and (3β,4β)‐24‐hydroxy‐16‐oxo‐28‐norolean‐12‐en‐3‐yl 4‐O‐β‐D ‐xylopyranosyl‐β‐D ‐glucopyranosiduronic acid ( 3 ), together with eight known constituents, i.e., the oleanane‐type triterpenoids 4 – 6 , and the ursane‐type triterpenoids 7 – 11 , were isolated from the spikes of Prunella vulgaris. The new structures were established by means of detailed spectroscopic analysis (IR, HR‐ESI‐MS, 1D‐ and 2D‐NMR experiments). Compounds 1 – 3 were tested for their inhibition activity against the growth of tumor cell lines; only compound 3 displayed marginal inhibition activity.     

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.     

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.     

Five New Eremophilane Sesquiterpenes from Ligularia przewalskii

Five new eremophilane‐type sesquiterpenes, 3β‐(acetyloxy)‐7‐hydroxynoreremophila‐6,9‐dien‐8‐one ( 1 ), 8β‐hydroxy‐2‐dehydroxyliguhodgsonal ( 2 ), 3β‐(acetyloxy)‐11‐methoxy‐8‐oxoeremophila‐6,9‐dien‐12‐oic acid ( 3 ), 3β‐(acetyloxy)‐11‐(2′‐methylbutanoyloxy)‐8‐oxoeremophila‐6,9‐dien‐12‐oic acid ( 4 ), and 3β‐(acetyloxy)‐6α‐hydroxyligularenolide ( 5 ), along with the three known compounds 6 – 8 , were isolated from the roots of Ligularia przewalskii. The structures of the new compounds were elucidated through spectral studies including HR‐EI‐MS, IR, and NMR data.     

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.     

Cytotoxic Diterpenoids from the Stem Bark of Annona squamosa L.

Three new ent‐kaurane diterpenoids, (4α)‐19‐nor‐ent‐kaurane‐4,16,17‐triol ( 1 ), (4α,16α)‐17‐(acetyloxy)‐19‐nor‐ent‐kaurane‐4,16‐diol ( 2 ), and 17‐hydroxy‐ent‐kaur‐15‐en‐19‐al ( 3 ), together with 11 known compounds, were isolated from the stem bark of Annona squamosa L. The structures of 1 – 3 were identified by analysis of their spectroscopic data. All compounds were evaluated for cytotoxic activity against human lung cancer (95‐D) and ovarian cancer (A2780) cell lines, and compounds 3, 5, 7, 11 – 14 exhibited promising antiproliferative activities with IC₅₀ values ranging from 0.38 to 34.66 μM .     

Six New Dammarane Triterpenoids from Viburnum cylindricum

One new dammarane triterpenoid, cylindrictone A ( 1 ), as well as five new nor‐dammarane triterpenoids cylindrictone B–F ( 2 – 6 ) were isolated from the leaves of Viburnum cylindrium, together with three known compounds 3β‐hydroxy‐hexanordammaran‐20‐one ( 7 ), 3α‐hydroxyoctanordammar‐12‐en‐17‐one ( 8 ), and neoalsogenin B ( 9 ). Their structures were identified by extensive NMR‐spectroscopic (especially 2D‐NMR) and mass‐spectrometric experiments, and the structure of 3 was further confirmed by a single‐crystal X‐ray analysis. The compounds exhibited no activity against human promyelocytic leukemia HL60 cell.