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1.
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‐Oβ‐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.  相似文献   

2.
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.  相似文献   

3.
Five new sesquiterpenoids, namely, 8β‐(angeloyloxy)‐4β,6α,15‐trihydroxy‐14‐oxoguaia‐9,11(13)‐dien‐12‐oic acid 12,6‐lactone ( 1 ), 4β,6α,15‐trihydroxy‐8β‐(isobutyryloxy)‐14‐oxoguaia‐9,11(13)‐dien‐12‐oic acid 12,6‐lactone ( 2 ), 11,12,13trinorguai‐6‐ene‐4β,10β‐diol ( 3 ), (1(10)E,4E,8Z)‐8‐(angeloyloxy)‐6α,15‐dihydroxy‐14‐oxogermacra‐(1(10),4,8,11(13)‐tetraen‐12‐oic acid 12,6‐lactone ( 9 ), and (1(10)E,4β)‐8β‐(angeloyloxy)‐6α,14,15‐trihydroxygermacra‐1(10),11(13)‐dien‐12‐oic acid 12,6‐lactone ( 11 ), and three new artifacts, (1(10)E,4Z)‐8β‐(angeloyloxy)‐9α‐ethoxy‐6α,15‐dihydroxy‐14‐oxogermacra‐1(10),4,11(13)‐trien‐12‐oic acid 12,6‐lactone ( 6 ), (1(10)E,4Z)‐8β‐(angeloyloxy)‐9α,13‐diethoxy‐6α,15‐dihydroxy‐14‐oxogermacra‐1(10),4‐dien‐12‐oic acid 12,6‐lactone ( 7 ), and (1(10)E,4Z)‐8β‐(angeloyloxy)‐9α‐ethoxy‐6α,15‐dihydroxy‐13‐methoxy‐14‐oxogermacra‐1(10),4‐dien‐12‐oic acid 12,6‐lactone ( 8 ), together with the three known sesquiterpenoids 4, 5 , and 10 , were isolated from the aerial parts of Siegesbeckia orientalis L. Their structures were established by spectral methods, especially 1D‐ and 2D‐NMR spectral methods.  相似文献   

4.
Six new compounds were isolated from the whole plant of Sonchus uliginosus, including three eudesmane‐type sesquiterpenoids (1β,6α)‐1,6,14‐trihydroxyeudesm‐3‐en‐12‐oic acid γ‐lactone ( 1 ), (1β,6α)‐1,6,14‐trihydroxyeudesma‐3,11(13)‐dien‐12‐oic acid γ‐lactone ( 2 ), and (1β,6α)‐1,6‐dihydroxy‐14‐O‐[(4‐hydroxyphenyl)acetyl]eudesma‐3,11(13)‐dien‐12‐oic acid γ‐lactone ( 3 ), and three phenylpropane derivatives, 4‐hydroxy‐γ,3,5‐trimethoxybenzenepropanol ( 6 ), γ,3,4,5‐tetramethoxybenzenepropanol ( 7 ), and γ,3,4,5‐tetramethoxybenzenepropanol acetate ( 8 ), together with the two known compounds 4 and 5 . The new structures were elucidated by means of spectroscopic methods, such as IR, EI‐MS, HR‐ESI‐MS, 1D‐ and 2D‐NMR, and by comparison of the spectroscopic data with those reported for structurally related compounds.  相似文献   

5.
Two new norditerpenoid alkaloids, habaenine A and B ( 1 and 2 ), together with two known compounds, were isolated from Aconitum habaense. The structures of the new compounds were elucidated on the basis of spectral analyses as (1α,6α,16β)‐8‐(acetyloxy)‐20‐ethyl‐13‐hydroxy‐1,6,16‐trimethoxy‐4‐(methoxymethyl)‐19‐oxoaconitan‐14‐yl 4‐methoxybenzoate ( 1 ) and (1α,6α,16β)‐8‐(acetyloxy)‐13‐hydroxy‐1,6,16‐trimethoxy‐4‐(methoxymethyl)‐aconitan‐14‐yl 4‐methoxybenzoate ( 2 ).  相似文献   

6.
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.  相似文献   

7.
A new triterpene, (3β,12β)‐taraxast‐20(30)‐ene‐3,12‐diol (=(3β,12β,18α,19α)‐urs‐20(30)‐ene‐3,12‐diol; 1 ), together with the known compounds ursolic acid, α‐amyrin, β‐amyrin, (2α,3β)‐2,3‐dihydroxyursa‐5,12‐dien‐28‐oic acid, (2α,3β)‐2,3,23‐trihydroxyurs‐12‐en‐28‐oic acid, (2S,3S,4R,8Z)‐1‐O‐(β‐D ‐glucopyranosyl)‐2‐{[(2R)‐2‐hydroxydocosanoyl]amino}octadec‐8‐ene‐1,3,4‐triol, and (2S,3S,4R,8Z)‐1‐O‐(β‐D ‐glucopyranosyl)‐2‐[(palmitoyl)amino]octadec‐8‐ene‐1,3,4‐triol, and quercetin 3‐(β‐D ‐glucopyranoside) were isolated from the leaves of Craibiodendron yunnanense. Their structures were established on the basis of spectral evidence. The last four compounds were identified for the first time in this plant.  相似文献   

8.
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.  相似文献   

9.
Four new podocarpane‐type trinorditerpenenes, (5β,10α)‐12,13‐dihydroxypodocarpa‐8,11,13‐trien‐3‐one ( 1 ), (5β,10α)‐12‐hydroxy‐13‐methoxypodocarpa‐8,11,13‐trien‐3‐one ( 2 ), (5β,10α)‐13‐hydroxy‐12‐methoxypodocarpa‐8,11,13‐trien‐3‐one ( 3 ), and (3α,5β,10α)‐13‐methoxypodocarpa‐8,11,13‐triene‐3,12‐diol ( 4 ), together with four known diterpenes, 12‐hydroxy‐13‐methylpodocarpa‐8,11,13‐trien‐3‐one ( 5 ), spruceanol ( 6 ), ent‐3α‐hydroxypimara‐8(14),15‐dien‐12‐one ( 7 ), and ent‐3β,14α‐hydroxypimara‐7,9(11),15‐triene‐12‐one ( 8 ), were isolated from the twigs and leaves of Aleurites moluccana. Their structures were elucidated by means of comprehensive spectroscopic analyses, including NMR and MS. Except 8 , all compounds were evaluated for their cytotoxicity; compound 4 exhibited moderate inhibitory activity against Raji cells with an IC50 value of 4.24 μg/ml.  相似文献   

10.
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.  相似文献   

11.
Four new triterpenoid glycosides named asiaticoside C ( 1 ), D ( 2 ), E ( 3 ), and F ( 4 ) were isolated from the BuOH fraction of the EtOH extract of whole plants of Centella asiatica, together with three known compounds, asiaticoside ( 5 ), madecassoside ( 6 ), and scheffuroside B ( 7 ). Based on FAB‐MS, IR, 1H‐ and 13C‐NMR, and 2D‐NMR data (HMQC, HMBC, COSY), the structures of the new compounds were determined as (2α,3β,4α)‐23‐(acetyloxy)‐2,3‐dihydroxyurs‐12‐en‐28‐oic acid Oα‐L ‐rhamnopyranosyl‐(1→4)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 1 ), (2α,3β)‐2,3‐dihydroxyurs‐12‐en‐28‐oic acid Oα‐L ‐rhamnopyranosyl‐(1→4)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 2 ), asiatic acid 6‐Oβ‐D ‐glycopyranosyl‐β‐D ‐glucopyranosyl ester ( 3 ), (3β,4α)‐3,23‐dihydroxyurs‐12‐en‐28‐oic acid Oα‐L ‐rhamnopyranosyl‐(1→4)‐Oβ‐D ‐glucopyranosyl‐(1→6)‐β‐D ‐glucopyranosyl ester ( 4 ).  相似文献   

12.
Two new diterpenoids, pedunculatic acid A (= (4R,5α,7α)‐7‐ethoxy‐9β,13β‐dioxyabiet‐8(14)‐en‐18‐oic acid; 1 ) and pedunculatic acid B (= (4S,5α,12β)‐8β,14β‐epoxy‐12‐hydroxy‐11‐oxototaran‐19‐oic acid; 2 ), together with three known sesquiterpenoids, were isolated from the Chinese medicinal herb Callicarpa pedunculata R. Brown . Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR, and by high‐resolution mass spectrometry.  相似文献   

13.
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.  相似文献   

14.
Phytochemical investigation of the 95% EtOH extract of the dry fronds of Conyza japonica (Thunb .) Less. resulted in the isolation of three new labdane diterpene glycosides, (3β,13S)‐13‐Oα‐L ‐rhamnopyranosyllabda‐8(17),14‐dien‐3‐yl α‐L ‐rhamnopyranoside ( 1 ), (3β,13S)‐13‐Oα‐L ‐rhamnopyranosyllabda‐8(17),14‐diene‐3‐yl 2‐O‐acetyl‐α‐L ‐rhamnopyranoside ( 2 ), and (3β,13S)‐13‐Oα‐L ‐rhamnopyranosylabda‐8(17),14‐dien‐3‐yl 6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→2)‐α‐L ‐rhamnopyranoside ( 3 ), together with their aglycone, (13S)‐labda‐8(17),14‐diene‐3,13‐diol ( 4 ). Their structures were characterized by spectroscopic analyses and chemical correlations, including 1D‐ and 2D‐NMR, and HR‐ESI‐MS. Furthermore, compounds 1 – 3 appeared to be promising as active agents against the tested pathogen fungi and oral pathogens as they possessed moderate cytotoxic properties.  相似文献   

15.
The two new triterpenoids, (5β,8α,9β,10α,13α,14β)‐5,9,13‐trimethyl‐4‐oxo‐3,24,25,26‐tetranor‐2,3‐secooleanane‐2,29‐dioic acid (=4‐oxo‐D:A‐friedo‐3‐nor‐2,3‐secooleanane‐2,29‐dioic acid; 1 ) and (2α,3β,4β,5β,8α,9tlsb=‐2%>β,10α,13α,14β,24R)‐3,24‐epoxy‐24‐ethoxy‐2‐hydroxy‐5,9,13‐trimethyl‐24,25,26‐trinoroleanan‐29‐oic acid (=3β,24‐ epoxy‐24α‐ethoxy‐2α‐hydroxy‐D:A‐friedooleanan‐29‐oic acid; 2 ) (absolute configurations tentative), together with a novel bi‐2H‐benzopyran, namely (rel‐(3R,3′S,4R,4′S)‐3,3′,4,4′‐tetrahydro‐6,6′‐dimethoxy[3,3′‐bi‐2H‐benzopyran]‐4,4′‐diol ( 3 ), were isolated from Tripterygium wilfordii Hook . f. Their structures were established by chemical and spectroscopic studies and by X‐ray crystallography.  相似文献   

16.
From the aerial parts of A. melanolepis, two new sesquiterpene lactones, melanolepin B ( = 1α,4β,8α‐trihydroxyeudesm‐11(13)‐en‐12,6α‐olide; 1 ) and melanolepin C (= 1α,10β‐epoxy‐8β‐hydroxygermacra‐4(15),11(13)‐dien‐12,6α‐olide; 2 ), were isolated, together with four known compounds, desacetyllaurenobiolide, dentatin A, taraxasterol, and (3S,5R)‐loliolide. Compound 1 was found to have the rare cis‐fused eudesmane skeleton. The structures of the isolated compounds were established by means of NMR (1H, 1H‐COSY, 1H,13C‐HSQC, HMBC, NOESY) and MS analyses.  相似文献   

17.
Investigation of the wood of Cunninghamia konishii resulted in the isolation and characterization of one new abietane diterpenoid, (6α,7β)‐7,8‐epoxy‐6‐hydroxyabieta‐9(11),13‐dien‐12‐one ( 1 ), and two new labdane diterpenoids, (12R)‐12‐hydroxylabda‐8(17),13(16),14‐trien‐19‐oic acid ( 2 ) and (12R)‐12‐hydroxylabda‐8(17),13(16),14‐trien‐18‐oic acid ( 3 ). The structures of these new compounds were elucidated by analysis of their spectroscopic data.  相似文献   

18.
Three new triterpenoids, (3β,8β,14α,21α)‐26,27‐dinoronocerane‐3,8,14,21‐tetrol ( 1 ), (3β,8β,14α,21β)‐26,27‐dinoronocerane‐3,8,14,21‐tetrol ( 2 ), and lycopodiin A ( 3 ), together with four known compounds, lycoclavanol ( 4 ), lycoclaninol ( 5 ), α‐onocerin ( 6 ), and 3‐epilycoclavanol ( 7 ), were isolated from Lycopodium japonicum Thunb (Lycopodiaceae). Their structures were established by means of spectroscopic analyses. Compounds 3 and 7 showed moderate antitumor activity. Compounds 4 and 6 exhibited acetylcholinesterase inhibition activity.  相似文献   

19.
The isolation and structure elucidation of two new oleanane‐type triterpene glycosides, 29‐(β‐D ‐glucopyranosyloxy)‐2α,3β,23‐trihydroxyolean‐12‐en‐28‐oic acid (=(2α,3β,4α,29α)‐29‐(β‐D ‐glucopyranosyloxy)‐2,3,23‐trihydroxyolean‐12‐en‐28‐oic acid; 1 ) and its C(20)‐epimer, 30‐(β‐D ‐glucopyranosyloxy)‐2α,3β,23‐trihydroxyolean‐12‐en‐28‐oic acid (=(2α,3β,4α,29β)‐29‐β‐D ‐glucopyranosyloxy)‐2,3,23‐trihydroxyolean‐12‐en‐28‐oic acid; 2 ), and a novel nortriterpene glycoside, (17S)‐2α,18β,23‐trihydroxy‐3,19‐dioxo‐19(18→17)‐ abeo‐28‐norolean‐12‐en‐25‐oic acid β‐D ‐glucopyranosyl ester (=(1R,2S,4aS,4bR,6aR,7R,9R,10aS,10bS)‐3,4,4a,4b,5,6,6a,7,8,9,10,10a,10b,11‐tetradecahydro‐1‐hydroxy‐7‐(hydroxymethyl)‐3′,4′,4a,4b,7‐pentamethyl‐2′,8‐ dioxospiro[chrysene‐2(1H),1′‐cyclopentane]‐10a‐carboxylic acid β‐D ‐glucopyranosyl ester; 3 ) from Phlomis viscosa (Lamiaceae) are reported. The structures of the compounds were asigned by means of spectroscopic (IR, 1D‐ and 2D‐NMR, and LC‐ESI‐MS) and chemical (acetylation) methods.  相似文献   

20.
Three new atisane diterpenoids, spiratisanins A – C ( 1  –  3 , resp.), featuring a phenylacryloxyl substituted ent‐atisane skeleton, were isolated from Spiraea japonica together with two known atisine diterpene alkaloids, spiramine A ( 4 ) and spiradine F ( 5 ). The structures of these new compounds were elucidated as (5β,7α,8α,9β,10α,12α,16β)‐16‐hydroxyatisan‐7‐yl (2E)‐3‐phenylprop‐2‐enoate ( 1 ), (5β,7α,8α,9β,10α,12α,16α)‐16‐hydroxyatisan‐7‐yl (2E)‐3‐phenylprop‐2‐enoate ( 2 ), and (5β,8α,9β,10α,12α,16β)‐16‐hydroxyatisan‐20‐yl (2E)‐3‐phenylprop‐2‐enoate ( 3 ) on the basis of spectroscopic analysis.  相似文献   

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