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1.
Studies on the chemical constituents of the flowers of Azadirachta indica have led to the isolation of two new flavanones, flowerine (=5‐hydroxy‐7,4′‐dimethoxy‐8‐(3‐methylbut‐2‐enyl)flavan‐4‐one; 1 ) and flowerone (=5,7,8,4′‐tetrahydroxy‐3′‐(3‐methylbut‐3‐enyl)flavan‐4‐one; 2 ), and two new triterpenoids, O‐methylazadironolide (=7α‐(acetoxy)‐23ξ‐methoxy‐21,23‐epoxy‐24,25,26,27‐tetranorapotirucalla‐1,14,20(22)‐trien‐3,21‐dione; 3 ) and diepoxyazadirol (=(20S,23S,24R)‐7‐α‐(acetoxy)‐25‐hydroxy‐21,24 : 23,24‐diepoxyapotirucalla‐1,14‐dien‐3‐one; 4 ) along with the known triterpenoid trichilenone acetate (=7α‐(acetoxy)‐14,15 : 21,23‐diepoxy‐24,25,26,27‐tetranorapotirucalla‐1,20,22‐trien‐3‐one; 5 ), two known flavanones, nimbaflavone (=5,7‐dihydroxy‐4′‐methoxy‐8,3′‐bis(3‐methylbut‐2‐enyl)‐flavan‐4‐one; 6 ) and 3′‐prenylnaringenin (=5,7,4′‐trihydroxy‐3′‐(3‐methylbut‐2‐enyl) flavan‐4‐one; 7 ), and 4‐(2‐hydroxyethyl)phenol ( 8 ). Their structures have been elucidated through spectral studies, including 2D‐NMR experiments, and chemical transformation. Compounds 5, 7 and 8 are heretofore unreported from any part of tree, while 6 has been isolated earlier from leaves.  相似文献   

2.
Six new compounds, including the two long‐chain esters balansenate I (=6,8,11‐trimethyldodecanoic acid (2E)‐3‐methylhexadec‐2‐enyl ester; 1 ) and balansenate II (=10,12,15‐trimethylhexadedecanoic acid (2E)‐3‐methylhexadec‐2‐enyl ester; 2 ), the eburicane‐like triterpenoid bridelone (=hexadecahydro‐4,4,10,13,14‐pentamethyl‐17‐(5‐methyl‐1,4‐dimethylenehexyl)‐3H‐cyclopenta[a]phenanthren‐3‐one; 3 ), the ‘deimino‐xanthine', bridelonine (=5‐(3‐methylbut‐2‐enyl)pyrrolo[3,4‐d]imidazole‐4,6(1H,5H)‐dione; 6 ), and the two adenine analogs 9‐(3‐methylbut‐2‐enyl)adenine ( 7 ) and 1‐(3‐methylbut‐2‐enyl)adenine ( 8 ), besides three known compounds, i.e., N6‐(3‐methylbut‐2‐enyl)adenine ( 4 ), 3‐(3‐methylbut‐2‐enyl)adenine ( 5 ), and adenine ( 9 ), were isolated from the leaves of Formosan Bridelia balansae. The novel skeleton of 6 consists of a fused pyrrolidine‐2,5‐dione and imidazole moiety. The already known adenines 7 and 8 were isolated for the first time from a plant. The structures of the isolated compounds were elucidated by spectroscopic analyses.  相似文献   

3.
An efficient method for the extraction of the carotenoids from Curtobacterium flaccumfaciens pvar poinsettiae was developed. The glucosides of C.p. 450 (=(all‐E,2R,2′R)‐2‐[4‐(β‐D ‐glucopyranosyloxy)‐3‐methylbut‐2‐enyl]‐2′‐(4‐hydroxy‐3‐methylbut‐2‐enyl)‐β, β‐carotene; 4 ) and of C.p. 473 (=(all‐E,2R,2′S)‐2‐[4‐(β‐D ‐glucopyranosyloxy)‐3‐methylbut‐2‐enyl]‐2′‐(3‐methylbut‐2‐enyl)‐3′,4′‐didehydro‐1′,2′‐dihydro‐β,ψ‐caroten‐1′‐ol; 5 ) were isolated for the first time. In addition, the hitherto unknown 3′,4′‐dihydro derivative of C.p. 450, called C.p. 460 (=(all‐E,2R,2′R)‐2‐(4‐hydroxy‐3‐methylbut‐2‐enyl)‐2′‐(3‐methylbut‐2‐enyl)‐1′,2′‐dihydro‐β,ψ‐caroten‐1′‐ol; 6 ), was identified. The structures were established by UV/VIS, CD, 1H‐ and 13C‐NMR, and mass spectra.  相似文献   

4.
Starting from readily available 7‐substituted 1‐indanones, products with a tetracyclo[5.3.1.01,704,11]undec‐2‐ene skeleton were obtained upon irradiation at λ=350 nm (eight examples, 49–67 % yield). The assembly of the structurally complex carbon framework proceeds in a three‐photon process comprising an ortho photocycloaddition, a disrotatory [4π] photocyclization, and a di‐π‐methane rearrangement. The flat aromatic core of the starting material is converted into a functionalized polycyclic hydrocarbon with exit vectors in three dimensions. Ring opening reactions at the central cyclopropane ring were explored, which enable the preparation of tricyclo[5.3.1.04,11]undec‐2‐enes and of tricyclo[6.2.1.01,5]undecanes.  相似文献   

5.
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 ).  相似文献   

6.
From the roots of Leontopodium alpinum, four new bisabolane sesquiterpenoids, (1R*,2S*,4R*,5S*)‐4‐(acetyloxy)‐2‐[3‐(acetyloxy)‐1,5‐dimethylhex‐4‐enyl]‐5‐methylcyclohexyl (2Z)‐2‐methylbut‐2‐enoate ( 1 ), (1R*,4S*,6R*)‐4‐(acetyloxy)‐6‐[3‐(acetyloxy)‐1,5‐dimethylhex‐4‐enyl]‐3‐methylcyclohex‐2‐en‐1‐yl (2Z)‐2‐methylbut‐2‐enoate ( 2 ), and 3‐methyl‐1‐{2‐[(1R*,2R*,5R*,6S*)‐2,5,6‐tris(acetyloxy)‐4‐methylcyclohex‐3‐en‐1‐yl]propyl}but‐2‐enyl (2Z)‐2‐methylbut‐2‐enoate ( 3 and 4 ) have been isolated. The latter constituents differ from each other by the relative configurations of the chiral centers of the hexenyl side chain.  相似文献   

7.
Two new compounds, mycorrhizin A and chloromycorrhizin A, have been isolated from a mycorrhizal fungus of Monotropa hypopitys, L. and their structures established as 1(S), 6(S),9(R) - 6 - hydroxy - 8,8 - dimethyl - 4 - (1 - chloro - prop -1 - enyl) - tricyclo[4.4.0.01.9] - 7 - oxa - dec - 3 - ene - 2,5 - dione and its 3-chloro derivative. Several derivatives were prepared and characterized.  相似文献   

8.
Three new neolignans, named 1‐deoxycarinatone ( 1 ), isodihydrocarinatidin ( 2 ), and isolicarin A ( 3 ), together with the known neolignan (+)‐dehydrodiisoeugenol ( 4 ), were isolated from mace (the aril of Myristica fragrans Houtt .). Their structures were elucidated as 2‐[(1S)‐2‐(4‐hydroxy‐3‐methoxyphenyl)‐1‐methylethyl]‐6‐methoxy‐4‐(prop‐2‐enyl)phenol ( 1 ), 4‐[(2R,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐(prop‐2‐enyl)benzofuran‐2‐yl]‐2‐methoxyphenol ( 2 ), and 4‐{(2S,3R)‐2,3‐dihydro‐7‐methoxy‐3‐methyl‐5‐[(1E)‐prop‐1‐enyl]benzofuran‐2‐yl}‐2‐methoxyphenol ( 3 ) on the basis of spectroscopic data.  相似文献   

9.
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.  相似文献   

10.
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.  相似文献   

11.
Five new compounds, including a novel lactone, machilactone (=rel‐(2R,3aR,6E,6aS)‐2‐heptadecyl‐3a‐methyl‐6‐octadecylidene‐6,6a‐dihydrofuro[2,3‐d][1,3]dioxol‐5(3aH)‐one; 1 ), a new sesquiterpene, 3,4‐dihydroxy‐β‐bisabolol (=rel‐(1R,2S,4R)‐1‐[(1R)‐1,5‐dimethylhex‐4‐enyl]‐1‐methylcyclohexane‐1,2,4‐triol; 2 ), a new secobutyrolactone, methyl (2E)‐2‐(1‐hydroxy‐2‐oxopropyl)eicos‐2‐enoate ( 3 ), two new butyrolactones, machicolide A ( 4 ) and machicolide B ( 5 ) (=3E,4R,5R)‐ and (3Z,4R,5R)‐4,5‐dihydro‐4‐hydroxy‐5‐methoxy‐5‐methyl‐3‐octadecylidenefuran‐2(3H)‐one, resp.) as a mixture, together with known caryophyllene oxide (=4,12,12‐trimethyl‐9‐methylene‐5‐oxatricyclo[8.2.0.04,6]dodecane), hexacosane, tetracosanoic acid, isomahubanolide‐23 (=(3E,4R)‐4,5‐dihydro‐4‐hydroxy‐5‐methylidene‐3‐octadecylidenefuran‐2(3H)‐one), and β‐bisabolol (=(1S)‐1‐[(1S)‐1,5‐dimethylhex‐4‐enyl]‐4‐methylcyclohex‐3‐en‐1‐ol) were isolated from the stem wood of Machilus zuihoensis. The structures of these compounds were established by spectroscopic studies. The eicos‐2‐enoate ( 3 ) and β‐bisabolol exhibited marginal cytotoxicity against NUGC and HONE‐1 cancer cell lines in vitro.  相似文献   

12.
Garciniaphenone (=rel‐(1R,5R,7R)‐3‐benzoyl‐4‐hydroxy‐8,8‐dimethyl‐1,7‐bis(3‐methylbut‐2‐en‐1‐yl)bicyclo[3.3.1]non‐3‐ene‐2,9‐dione; 1 ), a novel natural product, was isolated from a hexane extract of Garcinia brasiliensis fruits. The crystal structure of 1 as well as the selected geometrical and configurational features were compared with those of known related polyprenylated benzophenones. Garciniaphenone is the first representative of polyprenylated benzophenones without a prenyl substituent at C(5). Notably, the absence of a 5‐prenyl substituent has an impact on the molecular geometry. The tautomeric form of 1 in the solid state was readily established by a residual‐electronic‐density map generated by means of a difference Fourier analysis, and there is an entirely delocalized six‐membered chelate ring encompassing the keto–enol moiety. The configuration at C(7) was used to rationalize the nature of the keto–enol tautomeric form within 1 . The intermolecular array in the network is maintained by nonclassical intermolecular H‐bonds.  相似文献   

13.
A process‐scale stereoselective synthesis of nature‐identical (−)‐(S,S)‐7‐hydroxycalamenal (=(−)‐(5S,8S)‐5,6,7,8‐tetrahydro‐3‐hydroxy‐5‐methyl‐8‐(1‐methylethyl)naphthalene‐2‐carbaldehyde; (−)‐ 1a ) in 96% enantiomeric excess (ee) with the aid of chiral Ru complexes has been developed. The key step was the enantioselective hydrogenation of easily accessible 2‐(4‐methoxyphenyl)‐3‐methylbut‐2‐enoic acid ( 10 ) to (+)‐ 11 in a 86% ee (Scheme 5 and Table 1). A substantial increase in optical purity (96% ee) was achieved by induced crystallization of the intermediate (+)‐3,4‐dihydro‐4‐(1‐methylethyl)‐7‐methoxy‐2H‐naphthalen‐1‐one ((+)‐ 3 ). Computational conformation analysis carried out on the analog (−)‐ 9 rationalized the high diastereoselectivity achieved in the catalytic hydrogenation of the CC bond.  相似文献   

14.
A phytochemical investigation of the MeOH extract of Valeriana fauriei Briq . roots resulted in the isolation of two new sesquiterpenes, isovalerianin A (=(1β,4Z,6β,8α)‐8‐(acetyloxy)‐1,10‐dihydroxy‐6,11‐cyclogermacr‐4‐en‐15‐al=rel‐(1R,2Z,6S,7R,9R,10S)‐9‐(acetyloxy)‐6,7‐dihydroxy‐7,11,11‐trimethylbicyclo[8.1.0]undec‐2‐ene‐3‐carboxaldehyde; 1 ) and valerianin C (=(2α,3α,6α,8α)‐3‐(acetyloxy)‐2,4,8‐trihydroxyguai‐1(10)‐ene‐12,6‐lactone=rel‐(3R,3aS,4R,7S,8S,9R,9aR,9bR)‐8‐(acetyloxy)‐3a,4,5,7,8,9,9a,9b‐ octahydro‐4,7,9‐trihydroxy‐3,6,9‐trimethylazuleno[4,5‐b]furan‐2(3H)‐one; 2 ), together with six known compounds, i.e., camphor, methyl 4‐hydroxybenzoate, 2‐methoxybenzoic acid, benzoic acid, quercetin, and kaempferol. The structures of the compounds were established by detailed spectral analysis and comparison with previously reported data.  相似文献   

15.
Morpholine enamines 4‐acetyl‐4‐methyl‐1‐morpholinocyclohexene 4a, 4‐acetyl‐4‐phenyl‐1‐morpholinocyclohexene 4b, and 4‐acetyl‐4‐isopropenyl‐1‐morpholinocyclohexene 4c react with methacryloyl chloride to give 1,7‐dimethyl‐4(N‐morpholino) tricyclo[5.3.1.04,9]undecan‐2,6‐dione 9a , 1‐phenyl‐7‐methyl‐4(N‐morpholino) tricyclo[5.3.1.04,9]undecan‐2,6‐dione 9b , and 1‐ispropenyl‐7‐methyl‐4(N‐morpholino) tricyclo[5.3.1.04,9]undecan‐2,6‐dione 9c respectively, along with the corresponding substituted adamandane‐2,4‐diones.  相似文献   

16.
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.  相似文献   

17.
Seven new muurolane‐type sesquiterpenes, (4R,5R)‐muurol‐1(6),10(14)‐diene‐4,5‐diol (1), (4R,5R)‐muurol‐1(6)‐ene‐4,5‐diol (2), (4R,5R,10R)‐10‐methoxymuurol‐1(6)‐ene‐4,5‐diol (3), (4S)‐4‐hydroxy‐1,10‐seco‐muurol‐5‐ene‐1,10‐dione (4), (4R)‐4‐hydroxy‐1,10‐seco‐muurol‐5‐ene‐1,10‐dione (5), (6S,10S)‐6,10‐dihydroxy‐7,8‐seco‐2,8‐cyclo‐muurol‐4(5),7(11)‐diene‐12‐oic acid (6), and (6R,10S)‐6,10‐dihydroxy‐7,8‐seco‐2,8‐cyclo‐muurol‐4(5),7(11)‐diene‐12‐oic acid (7) were isolated from the marine sponge Dysidea cinerea. Their structures were determined by the combination of spectroscopic and chemical methods, including 1D‐NMR, 2D‐NMR, and CD spectra as well as by comparing the NMR data with those reported in the literature. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

18.
Both (intermolecular) photocycloadditions of 2H‐1‐benzopyran‐ and 2H‐1‐benzothiopyran‐3‐carbonitriles to 2,3‐dimethylbut‐2‐ene and 2‐methylbut‐1‐en‐3‐yne, and (intramolecular) photoisomerization of 4‐(alkenyl)benzopyran‐3‐carbonitriles were investigated. In contrast to 2H‐1‐benzopyran‐3‐carbonitrile ( 1 ), its thia analog 4 reacts with 2,3‐dimethylbut‐2‐ene selectively, to afford only cyclobuta derivative 7 . In the presence of 2‐methylbut‐1‐en‐3‐yne, both 1 and 4 behave alike to afford the all‐cis‐cyclobuta diastereoisomers, 15 and 8 , respectively, as main products, as well as minor amounts of cyclobutenes 17 and 10 , respectively, which result from the addition of the terminal C‐atom of the acetylenic bond to C(3) of the heterocycle. 4‐Methyl‐2H‐1‐benzopyran‐3‐carbonitrile ( 5 ) does not undergo photoaddition to the alkene or the alkenyne mentioned above, whereas the corresponding intramolecular [2+2] photocycloaddition of 4‐(pent‐4‐enyl)benzopyran‐3‐carbonitrile ( 6b ) to tetracycle 20 proceeds quantitatively.  相似文献   

19.
The EtOH extract of dried root bark of Tripterygium wilfordii Hook. f. (Celastraceae) afforded a novel macrolactone cyclopeptide named triptotin L (=cyclo[L ‐alanyl‐L ‐alanyl‐3‐(4,4,9‐trimethyldecyl‐3‐hydroxypropanoylglycyl‐L ‐valyl‐L ‐leucyl; 1 ), the new triterpene 2β,6α,22β‐trihydroxy‐24,29‐dinor‐D:A‐friedoolean‐4‐ene‐3,21‐dione named 6α‐hydroxytriptocalline A (=(2β,6α,8α,9β,10α,13α,14β,20β,22β)‐2,6,22‐trihydroxy‐9,13‐dimethyl‐24,25,26,30‐tetranorolean‐4‐ene‐3,21‐dione; 2 ), the new diterpenoid 11,16‐dihydroxy‐14‐methoxy‐18(4→3) abeo‐abieta‐3,8,11,13‐tetraene‐18‐oic acid named 16‐hydroxytriptobenzene H (=(4aS,10aS)‐3,4,4a,9,10,10a‐hexahydro‐5‐hydroxy‐7‐(2‐hydroxy‐1‐methylethyl)‐8‐methoxy‐1,4a‐dimethylphenanthrene‐2‐carboxylic acid; 3 ), and the abietane diterpenoid alkaloid named triptotin J (=(7aS,11aS,11bS)‐7,7a,8,9,10,11,11a,11b‐octahydro‐11b‐hydroxy‐α,α,8,8,11a‐pentamethyl‐6H‐naphth[1,2‐d]azepine‐4‐methanol; 4 ). Their structures were established on the basis of spectroscopic studies.  相似文献   

20.
Four new prenylindole derivatives, (R)‐6‐(2,3‐dihydroxy‐3‐methylbutyl)indole (1), (R)‐6‐(2,3‐dihydroxy‐3‐methylbutyl)indolin‐2‐one (2), and an unseparated mixture of (Z)‐6‐(4‐hydroxy‐3‐methylbut‐2‐en‐1‐yl)indolin‐2‐one (3a) and (E)‐6‐(4‐hydroxy‐3‐methylbut‐2‐en‐1‐yl)indolin‐2‐one (3b) with a ratio of 3 : 2, were isolated from the culture broth of a streptomycete isolated from Ailuropoda melanoleuca feces. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic techniques. The absolute configuration of 1 was determined by Mosher's method. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

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