6H-二苯并[b,d]吡喃-6-酮及其衍生物的合成方法研究进展

6H-二苯并[b,d]吡喃-6-酮类化合物因其广泛的生物活性以及荧光性能而越来越受到化学家们的关注。本文综述了6H-二苯并[b,d]吡喃-6-酮类化合物的主要合成方法,包括分子内关环法、碳氢键活化法、合成苯环法、氧化法,并比较了这四类合成方法的优缺点。今后,如何高效、经济、绿色地合成在特定位置含特定取代基的6H-二苯并[b,d]吡喃-6-酮及其类似物,仍是天然产物合成领域的一个重大课题。     

Decarboxylation in proton acceptor solvents

Heating 3,8-dinitro-10-carboxy-6H-dibenzo[b,d]pyran-6-one in DMSO, DMF, or HMPTA leads to decarboxylation and the replacement of the carboxyl group by a hydroxy group with the formation of 3,8-dinitro-6H-dibenzo[b,d]pyran-6-one and 3,8-dinitro-10-hydroxy-6H-dibenzo [b,d]pyran-6-one. The decarboxylation of 2,7-dinitro-5,10-dioxo-4,5,9,10-tetrahydro-4,9-dioxapyrene in HMPTA is preceded by opening of the two lactone rings and the formation of a 1:4 molecular complex of 4,4-dinitro-6,6-dihydroxy-2,2-dicarboxybiphenyl with HMPTA, whose structure was established by x-ray diffraction structural analysis.Translated from Khimiya Geterotsiklicheskik Soedinenii, No. 2, pp. 164–170, February, 1989.     

The complete gene cluster of the antitumor agent gilvocarcin V and its implication for the biosynthesis of the gilvocarcins

Gilvocarcin V, an antitumor agent produced by the bacterium Streptomyces griseoflavus G? 3592, is the most studied representative of the distinct family of benzo[d]naphtho[1,2-b]pyran-6-one aryl C-glycoside antibiotics, which show excellent antitumor activity and a remarkably low toxicity. Its biosynthesis contains many intriguing steps, including an oxidative rearrangement, the C-glycosylation, and the generation of a vinyl side chain. These steps all contribute to structural elements of the drug, which are essential for its biological activity, but only poorly understood. Herein we report the cloning and characterization of the gilvocarcin (gil) gene cluster from S. griseoflavus G? 3592, and its heterologous expression in a foreign host (S. lividans). This is the first reported gene cluster encoding the biosynthesis of a benzo[d]naphtho[1,2-b]pyran-6-one aryl C-glycoside antibiotic, which not only provides insights regarding the biosynthesis of gilvocarcin V but also lays the foundation for the detailed studies of its intriguing biosynthetic steps and possibly for the generation of gilvocarcin analogues with improved biological activities through combinatorial biosynthesis.     

Two new iridoids from roots of Patrinia scabra Bunge

Two new iridoids 1,3-dimethyloxy-7-hydroxymethyl-4-(3-methyl-butyryloxymethyl)-1-hydrocyclopenta-4,7-diene[c]pyran-6-one (1) and 1,3-dimethyloxy-7-hydroxymethyl-4-methyloxymethyl-1-hydrocyclopenta-4,7-diene[c]pyran-6-one (2) were isolated from the roots of Patrinia scabra Bunge. The structure elucidation of the isolated compounds was based primarily on HRESIMS, EIMS, IR, UV, 1D- and 2D-NMR analyses, including COSY, HMQC, HMBC and NOESY correlations, as well as X-ray crystallographic analysis.     

Regioselective Heterocyclization of 3-(Cyclohex-2′-enyl)-4-hydroxy-6-methylpyran-2-one

Summary.  Regioselective heterocyclization of 3-(cyclohex-2′-enyl)-4-hydroxy-6-methyl pyran-2-one with various reagents afforded different heterocycles. With N-iodosuccinimide in acetonitrile at 0–5°C it gave 6-methyl-9′-iodo-2′-oxabicyclo[3.3.1]nonano[3,2-c]pyran-2-one, with C₅H₅NHBr₃ or C₆H₁₂N₄HBr₃ in CHCl₃ at 0–5°C it furnished 6-methyl-9′-bromo-2′-oxabicyclo[3.3.1]nonano[3,2-c]pyran-2-one. Cold concentrated H₂SO₄ lead to 6-methyl-2′-oxabicyclo[3.3.1]nonano[3,2-c]pyran-2-one, whereas PdCl₂(PhCN)₂ in C₆H₆ at 80°C afforded 9-methyl benzofuro[3,2-c]pyran-2-one. Corresponding author. E-mail: kcm@klyuniv.ernet.in Received December 27, 2001. Accepted (revised) March 1, 2002     

Synthèse de flavones et de xanthones dans la série du benzo[4,5]thiophène

We describe the first synthesis of 2-arylbenzo[4,5]thieno-[2,3-b]pyran-4-one and of 2-arylbenzo [4,5] thieno [3,2-b] pyran-4-one, from benzo [4,5] thiophene and we have extended these cyclizations to obtain the heterocyclic analogs of the xanthones.     

Synthesis and reactions of 2-(dimethylaminomethylidene)-6-methoxynaphto[1,8-<Emphasis Type="Italic">bc</Emphasis>]pyran-3-one

The reaction of 6-methoxynaphthol[1,8-bc]pyran-3-one with dimethylformamide dimethyl acetal gave the corresponding 2-dimethylaminomethylidene derivative which reacted with amines to form new 2-aminomethylidene-6-methoxynaphtho[1,8-bc]pyran-3-ones via replacement of the dimethylamino group. 2-Dimethylaminomethylidene-6-methoxynaphtho[1,8-bc]pyran-3-one also reacted with 2,3-dimethylchromenium perchlorate and 1,2,3,3-tetramethyl-3H-indolium perchlorate to give the corresponding merocyanine dyes. The latter were examined for chemosensor and photochromic properties.     

Synthesis of nitro-substituted dioxotetrahydrodioxapyrenes and 6H-dibenzo[b,d]pyran-6-one

Methods for the synthesis of tri- and tetranitro-substituted 5,9-dioxo-4,5,9,10-tetrahydro-4,10-dioxapyrenes, 5,10-dioxo-4,5,9,10-tetrahydro-4,9-dioxapyrenes, and 6H-dibenzo[b,d]pyran-6-one were developed in a search for effective sensitizers for electrophotographic layers based on carbazole-containing polymers. The possibility of the production of nitro compounds that contain three vicinal nitro groups was demonstrated. Under severe nitration conditions 2,4,8-trinitro-6H-dibenzo[b,d]pyran-6-one is cleaved to give 2-hydroxy-2-carboxy-3,5,4-trinitro-biphenyl, which is resistant to cyclization to give the starting compound, evidently because of the existence of an intramolecular hydrogen bond between the hydroxy group and the nitro group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 463–467, April, 1985.     

Furannes et pyrroles disubstitués en 2,3. XVI synthèse de furo[3,2-c]pyranones-4 et nouvelle voie d'accès aux furo[3,2-c]pyridines

Treatment of 4-hydroxy-6-methylpyran-2-one with chloracetalhyde in basic aqueous medium gave 6-methylfuro[3,2-c]pyran-4-one. This compound reacted with ammonium hydroxide and some primary amines to form the corresponding N-substituted furo[3,2-c]pyrid-4-ones which may also be obtained from 4-hydroxy-α-pyridones. Furo[3,2-c]pyran-4-one was acylated at the 2 position and 4-chloro-6-methylfuro[3,2-c]pyridine easily gave 4-substituted derivatives by displacement of the halogen atom.     

Synthesis,Crystal Structure and Properties of Ethyl 3,9-Dimethyl-7-phenyl- 6H-dibenzo[b,d]pyran-6-one-8-carboxylate

Ethyl 3,9-dimethyl-7-phenyl-6H-dibenzo[b,d]pyran-6-one-8-carboxylate(C24H20O4, Mr = 372.40) has been synthesized and its structure was determined by 1H and 13C NMR, ESI-MS, elemental analysis, and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/n, with a = 8.3674(11), b = 10.6683(14), c = 11.3817(15) , α = 95.596(2), β = 109.866(2), γ = 94.495(2)°, V = 944.2(2)3, Z = 2, Dc = 1.310 g/cm3, μ = 0.089 mm-1, F(000) = 392, R = 0.0482 and wR = 0.1281 for 2916 observed reflections with I 2σ(I). In the crystal structure, the fused tricyclic nucleus of the title compound is not fully coplanar. Analysis of the crystal packing indicates aromatic π-π stacking interactions occurring between the fused tricyclic aromatic rings of neighboring molecules in which a maximum overlap of the π-electron systems was achieved. Fluorescence and thermal studies indicate that compound 3 has good optical properties and thermal stability.     

Cytotoxic metabolites from the Okinawan ascidian Diplosoma virens

The unstable isomeric compounds 5-hydroxy-7-prop-2-en-(E)-ylidene-7,7adihydro-2H-cyclopenta[b]pyran-6-one (1) and 5-hydroxy-7-prop-2-en-(Z)-ylidene-7,7adihydro-2H-cyclopenta[b]pyran-6-one (2), previously described as antimicrobial metabolites from the sponge Ulosa sp., were isolated and identified as major components of the ascidian Diplosoma virens. In this paper, full spectral data for 2 and complete 13CNMR data for 1, based on 2D NMR measurements, are provided for the first time. Compounds 1 and 2 showed cytotoxity against HCT116 cells (human colorectal cancer cells) by triggering apoptotic cell death.     

3-取代卓酚酮5位偶联产物的溴氧化成环反应

报道了采用溴氧化3-异丙烯基卓酚酮和3-肉桂酰基卓酚酮合成杂环并卓酮化合物的新方法。3-异丙烯基卓酚酮5位偶联产物1a-1f和3-肉桂酰基卓酚酮5位偶联产物3a-3d分别在吡啶介质中与过量溴作用生成5-取代苯偶氮基-7-溴-3-甲基-8-氢环庚并呋喃-8-酮2a-2f和6-取代苯偶氮基-2-苯基-8-溴-4,9-二氢环庚并吡喃-4,9-二酮4a-4d。     

Synthesis of a rotenone-like benzopyranobenzopyranone

The synthesis of a novel rotenone-like molecule, 9-methoxy-8-methyl-6,6a,12,12a-tetrahydro[1]benzopyrano-[3,4-b][1]benzopyran-12-one ( 2 ) is described. Efficient syntheses of 3,4-dihydro-2H-[1]benzopyran-3-one ( 9 ) from ethyl 3-hydroxy-2H-[1]benzopyran-4-carboxylate ( 6 ), an intermediate in the synthesis of 2 , were developed. Thermolysis of 6 and 9 in decalin yielded 6,8-dihydro-14H-bis[1]benzopyrano[3,4-b:4′,3′-e]pyran-14-one ( 8 ), which has previously been described. Also produced in the thermolysis was the isomeric 1H-bis[1]-benzopyrano[3,4-b:3′,4′-á]pyran-7-(9H)one ( 10 ), the first member of a novel, pentacyclic ring system.     

Action de réactifs nucléophiles sur les phényl-5 thiéno[3,2-b]pyrannone-7 et phényl-2 benzo[b]thiéno[3,2-b]pyrannone-4

Reactions of 5-phenylthieno[3,2-b]pyran-7-one, 2-phenylbenzo[b]-thieno[3,2-b]pyran-4-one and the corresponding thiones with sodium ethylate, guanidines, hydrazines and amines are described and compared to those observed with benzopyranones.     

水介质中吡喃并[3,2-c]吡喃-5-酮衍生物的三组分一锅合成

水介质中在氯化三乙基苄基铵(TEBAC)催化下, 芳醛与丙二腈和4-羟基-6-甲基吡喃-2-酮三组分一锅反应合成了一系列2-氨基-3-氰基-4-芳基-4H,5H-吡喃-5-酮. 该反应具有产率高、污染少、操作简单、环境友好等优点.     

A new iridoid compound from Patrinia rupestris (Pall.) Juss

Extraction of roots of Patrinia rupestris (Pall.) Juss. gave a new iridoid compound, 1β,3α-diethyloxy-7-hydromethyl-4-(3-methyl-butyryloxymethyl)-cyclopenta-4(4a),7(7a)-diene[c]pyran-6-one (1), together with a known compound, (1α,4aα,?6α,7β,7aα)-[4a,5,6,7,7a-hexahydro-6,7-dihydroxy-1-(3-methyl-1-oxobutoxy) cyclopenta[c]pyran-4,7-diyl]bis(methylene) 3-methyl-butanoic acid ester (2). The structure of 1 was characterised by HRESIMS, IR, UV, 1-D NMR and 2-D NMR methods. Compound 2 was isolated from this genus for the first time.     

Synthesis and structure of heterocyclic derivatives of pyran-2-ones based on the dimer of 4,6-di(<Emphasis Type="Italic">tert</Emphasis>-butyl)-3-hydroxy-1,2-benzoquinone

Acid-catalyzed reaction of 6,10a-dihydroxy-3,4a,7,9-tetra(tert-butyl)-1,2,4a,10a-tetrahydrodibenzo-[b,e][1,4]dioxine-1,2-dione with 2-methylquinoline derivatives led to the formation of a previously unknown system 6-[(Z)-2-(quinolin-2-yl)-1-hydroxyethen-1-yl]pyran-2-one. The molecular structure of 3,5-di(tert-butyl)-6-[(Z)-2-(7,8-dimethyl-4-chloroquinolin-2-yl)-1-hydroxyvinyl]pyran-2-one was established by XRD method; the energy and structural characteristics of its isomers in the gas phase and in a polar solvent were calculated by quantumchemical methods (B3LYP/6-31G**).     

Synthesis of 6H-dibenzo[b,d]pyran-6-ones from aryl 3-bromopropenoates via a sequential one-pot procedure using the Sonogashira coupling-benzannulation reaction

Various kinds of 6H-dibenzo[b,d]pyran-6-ones 4 were synthesized via a sequential one-pot procedure using the Sonogashira coupling-benzannulation reaction of aryl 3-bromopropenoates 1, in which the ortho-position of aryl group is substituted with enynes or iodine, with acetylenes 2 in the presence of palladium and copper catalysts. The Sonogashira coupling between the aryl 3-bromopropenoates 1a and 1b, bearing enynes at the ortho-position of aryl group, and alkynes 2a-g gave the enyne intermediates 3 in situ, which subsequently underwent the palladium-catalyzed benzannulation reaction to afford the 6H-dibenzo[b,d]pyran-6-ones 5a-g and 6. The Sonogashira coupling between the aryl 3-bromopropenoate 1c, bearing iodine at the ortho-position of aryl group, and diynes 2f and 2h produced the diyne intermediates 13, which underwent the benzannulation reaction to afford the 6H-dibenzo[b,d]pyran-6-ones 14f and 14h.     

Synthesis of (±)-8-deisopropyladunctin B

(±)-8-Deisopropyladunctin B, the deisopropyl form of adunctin B, which was isolated from the leaves of Piper aduncum (Piperaceae) collected in Papua New Guinea, was synthesized in 0.77% overall yield in 17 steps from 5,7-dimethoxycoumarin-3-carboxylate. The key step was our original stereoconvergent skeleton transformation from 1,2,2a,8b-tetrahydro-3H-benzo[b]cyclobuta[d]pyran-3-one to 1,2,4a,9b-tetrahydrodibenzofuran-4-ol with dimethylsulfoxonium methylide.     

A new regioselective synthesis of 2,3,4,5-tetrahydro-6H-oxepino[3,2-c]pyran-6-ones,and [1]benzopyran-6-ones

Through an anti-Markovnikow hydration of some olefin derivatives of 4-hydroxy-2-pyrones, and 4-hydroxy-coumarins, followed by a regioselective intramolecular dehydration, involving the primary alcohols obtained and the enolic oxygen of the rings, promoted by Amberlyst 15 in boiling toluene, the new heterocycles 2,3,4,5-tetrahydro-6H-oxepino[3,2-c]pyran-6-one ( 3 ) and [1]benzopyran-6-ones ba,c were obtained in fair yields.