A novel chromone-substituted trimeric dihydroflavonol from <Emphasis Type="Italic">Anogeissus pendula</Emphasis>

A new chromone-substituted dihydrotriflavonol, (2S,3S)[6-{(3S) 3″,5″-dihydroxy-6″-methoxydihydrochromone}5,3′,4′,5′-tetrahydroxy-7-methoxy-3-O-8-dihydroflavone]₂ 3-O-8[6-{(3S) 3″,5″-dihydroxy-6″methoxydihydrochromone}3,5,3′,4′,5′-pentahydroxy-7-methoxydihydroflavonol] was isolated from the leaves of Anogeissus pendula. The structure was determined by UV, ¹H NMR, ¹³C NMR, HMBC, and CD data.     

Reaction of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine,quinolin-8-amine,and 1,3-diketones

Condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and cyclohexane-1,3-dione, methyl 2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone gave the corresponding 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydro-12H-benzo[c]acridin-8-ones. The reaction of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and indan-1,3-dione produced 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-8H-benzo[h]indeno[1,2-b]quinolin-8-one. 7-(2′-Hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydrobenzo[b][1,10]phenanthrolin-8-ones were obtained by three-component condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with quinolin-8-amine and cyclohexane-1,3-dione, methyl 2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone.     

4,6-Dimethylpyridine-2,3-dicarbonitrile and its reaction with <Emphasis Type="Italic">N</Emphasis>-acylhydrazines

An efficient method has been developed for the synthesis of 4,6-dimethylpyridine-2,3-dicarbonitrile. A study was carried out on the reaction of this compound with N-acylhydrazines to give two structural isomers, namely, N′-(7-amino-2,4-dimethyl-5H-pyrrolo[3,4-b]pyridin-5-ylidene)carbohydrazides and N′-(5-amino-2,4-dimethyl-7H-pyrrolo[3,4-b]pyridin-7-ylidene)carbohydrazides as well as disubstituted N′,N″-(2,4-dimethyl-5H-pyrrolo[3,4-b]pyridine-5,7-diylidene)dicarbohydrazides.     

New synthesis of ( E )-3,7-dimethyl-2,7-octadienylpropionate and ( E )-3,7-dimethyl-2-octen-1,8-diol, pheromone components of San Jose scaleinsect Quadraspidiotus pernicious and african monarch butterfly Danaus chrysippus

6-Methyl-6-hepten-2-one (3) on reaction with ethyl α-dimethylphosphonate/NaH gives a mixture of (E)-and (Z)-conjugated esters. The major (E)-isomer, (E)-ethyl-3,7-dimethyl-2,7-octadienoate (4), on reduction with LiAlH₄ at room temperature furnishes (E)-3,7-dimethyl-2,7-octadien-l-ol (5) which on propionylation affords (E)-3,7-dimethyl-2,7-octadienyl propionate (1). Carbinol (5) is converted into its silyl ether (E)-2,6-dimethyl-8-t-butyldimethylsilyloxy-l,6-octadiene (6) witht-Bu(Me)₂SiCl in CH₂Cl₂, which on hydroboronation-oxidation with 9-BBN/NaOH-H₂O₂ followed by disilylalion with (n-Bu)₄N⁺ F⁻ at room temperature, gives (E)-3,7-dimethyl-2-octen-l,8-diol (2).     

Five-membered 2,3-dioxo heterocycles: LXXVI. Reaction of methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione

Methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione to give methyl 11-aryl-12-benzoyl-9-hydroxy-4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetraazatricyclo[7.2.1.0^2,7]dodec-2(7)-ene-1-carboxylates which underwent thermal recyclization to 1-aryl-3-benzoyl-4-hydroxy-1′,3′-dimethylspiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraones.     

New steroidal glycosides from the stem bark of <Emphasis Type="Italic">Mimusops elengi</Emphasis>

Two new steroidal glycosides (1 and 2) have been isolated from the ethanolic extract of the stem bark of Mimusops elengi L. and characterized as stigmasta-5,22-dien-3β-ol-3β-D-glucuropyranosyl-(6′β→1″)-D-glucopyranoside (1) and β-sitosterol-3β-(3″′,6″′,7″′-trihydroxynaphthyl-2″′-carboxyl)-4″-glucopyranosyl-(1″→4′)-glucopyranoside (2) along with the known compounds stigmasta-5-en-3β-ol, lup-20(29)-en-3β-ol, and stigmasta-5-en-3β-D-glucopyranoside. Their structures have been elucidated on the basis of spectral data analysis and chemical reactions.     

[3,4]-annulated pyrroles 1. Polynuclear heterocyclic systems based on pyrrolo[3,4-d]pyrimidine-2,4-dione

The intramolecular electrophilic substitution in 6-functionalized 1,3-dimethyl-1H-pyrrolo[3,4-d]pyrimidine-2,4(3H,6H)-diones was used for the synthesis of pyrimido[4′,5′:3,4]-pyrrolo[1,2-a]quinoxaline-8,10(7H,9H)-dione, pyrimido[4′,5′:3,4]pyrrolo[2,1-c][1,2,4]benzo-triazine-8,10(7H,9H)-dione, and 2H-pyrimido[4′,5′:3,4]pyrrolo[1,2-a]indole-2,4,11(1H, 3H)-trione derivatives. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2180–2185, December, 2006.     

Two new myricetin glycosides from pine needles of <Emphasis Type="Italic">Cedrus deodara</Emphasis>

Two new myricetin glycosides, myricetin-3-O-(6″-O-E-p-coumaroyl)-α-D-glucocopyranoside (1) and 3′,5′-di-O-methylmyricetin-3-O-(6″-O-acetyl)-α-D-glucopyranoside (2), and three known flavonoids, myricetin (3), cedrin (4), and 2R,3R-dihydromyricetin (5), were isolated from the pine needles of Cedrus deodara. Their structures were elucidated on the basis of extensive spectroscopic analysis and chemical evidence.     

Dibenzo-18-crown-6 modified with kojic acid fragments

Diazonium salts were prepared by diazotization of 4′-amino-, 4′,4″-, and 4′,5″-diaminodibenzo-18-crown-6. Their coupling products with kojic acid (5-hydroxy-2-hydroxymethyl-γ-pyrone) were synthesized for the first time: 4′-(6-aza-5-hydroxy-2-hydroxymethyl-γ-pyronyl)-, 4′,4″-di-(6-aza-5-hydroxy-2-hydroxymethyl-γ-pyronyl)-, and 4′,5″-di-(6-aza-5-hydroxy-2-hydroxymethyl-γ-pyronyl)-dibenzo-18-crown-6. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 415–416, September–October, 2006.     

An efficient method for the synthesis of 9-β-D-2′-deoxyribofuranosyl-6-methylpurine

A new method for the preparation of 9-β-D-2′-deoxyribofuranosyl-6-methylpurine from inosine (1) is described. Inosine was converted to 6-chloropurinenucleoside (4) via acetylation, chlorination, and deacetylation. Compound 4 was transformed to the key intermediate 6-methylpurinenucleoside (7) via protection of the 2′,3′,5′-hydroxy groups of 4 with 3,4-dihydropyran to give compound 5, then methylation at the 6-position of 5 with dimethyl copper lithium gave compound 6; depyranylation of 6 led to the subsequent selective protection of the 3′,5′-hydroxy groups of 7 with O[Si(I-Pr)₂Cl]₂ followed by reaction with phenyl chlorothionoformate to give compound 9. Compound 9 was then converted to the target compound 11 via 2′-deoxidation and 3′, 5′-desilylation. The structures of these products were identified by Mass Spectrum (MS), ¹H-NMR (Nuclear Magnetic Resonance) spectra and elemental analysis. Translated from Chinese Journal of Organic Chemistry, 2006, 26(10): 1394–1397 (in Chinese)     

Polyphenols and acids of Ulugbekia tschimganica

From the herbage ofUlugbekia tschimganica (B. Fedtsch.) Zak two new phenolcarboxylic acids have been isolated in the form of their methyl derivatives: methyl ulugbekate C₁₉H₁₈O₆ (I) and methyl ulugbinate acid C₂₀H₂₂O₇ (II), mp 228°C. It has been established that (I) most probably has the structure of 1,5-bis(3′,4′-dihydroxyphenyl)-3-methoxycarbonylpent-1-ene and (II) that of 1,5-bis(2′,4′-dihydroxyphenyl)-3-methoxycarbonylpent-1-ene and (II) that of 1,5-bis(2′,4′-dihydroxyphenyl)-3-methoxycarbonyl-4-methoxypent-2-ene.     

Phototransformations of 4,5-diphenylisoxazole

Sunlight photolysis of 4,5-diphenylisoxazole (1) in methanol sensitized by benzophenone gives 4,4′,5,5′-tetraphenyl-2,2′-bioxazole, (4). On irradiation at 350nm in acetone or at 253.7 nm in absolute alcohol, isoxazole (1) yields α-benzoylphenylacetonitrile (6) besides the expected phenanthro [9,10-d]-oxazole (5). The bioxazole and the ketonitrile have been identified by single crystal X-ray studies.     

Synthesis,Spectra and Electrochemistry of Dinitro-bis-{1-alkyl-2-(arylazo) imidazole} Ruthenium(II). Nitro-nitroso Derivatives and Reactivity of the Electrophilic {Ru-NO}<Superscript>6</Superscript>System

Ag⁺ assisted aquation of blue cis-trans-cis-RuCl₂(RaaiR′)₂ (4–6) leads to the synthesis of solvento species, blue-violet cis-trans-cis-[Ru(OH₂)₂(RaaiR′)₂](ClO₄)₂ [Raai R′=p-R-C₆H₄ N=N–C₃H₂–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), OMe (b), NO₂ (c) and R′ = Me (1/4/7/10), CH₂CH₃ (2/5/8/11), CH₂Ph (3/6/9/12)] that have been reacted with NO₂⁻in warm EtOH resulting in violet dinitro complexes of the type, Ru(NO₂)₂(RaaiR′)₂ (7–9). The nitrite complexes are useful synthons of electrophilic nitrosyls, and on triturating the compounds, (7b–9b) with conc. HClO₄ nitro-nitrosyl derivatives, [Ru(NO₂)(NO)(OMeaaiR′)₂](ClO₄)₂ (10b–12b) are isolated. The solution structure and stereoretentive transformation in each step have been established from ¹H n.m.r. results. All the complexes exhibit strong MLCT transitions in the visible region. They are redox active and display one metal-centred oxidation and successive ligand-based reductions. The redox potentials of Ru(III)/Ru(II) (E_1/2^M) of (10b–12b) are anodically shifted by ∼ ∼0.2 V as compared to those of dinitro precursors, (7b–9b). The ν(NO) >1900 cm⁻¹ strongly suggests the presence of linear Ru–NO bonding. The electrophilic behaviour of metal bound nitrosyl has been proved in one case (12b) by reacting with a bicyclic ketone, camphor, containing an active methylene group and an arylhydrazone with an active methine group, and the heteroleptic tris chelates thus formed have been characterised.     

Solid-state structure of (+)-phendimetrazine bitartarate,an anorexic drug

The anorexic drug (+)-(2S, 3S, 4S)-phendimetrazine-2R, 3R)-bitartarate crystallized in the orthorhombic space groupP2₁2₁2₁ and at 293 Ka=7.7710(4),b=13.1379(7),c=15.9913(9) Å,V=1632.6(2) ų,Z=4,R(F)=0.062, andR _w (F)=0.026. A chair conformation 2,3-trans-1,4-oxazine ring with equatorially oriented 2-phenyl,3-methyl, andN-methyl substituents was found as predicted by an earlier reported solid-state CP-MAS¹³C-NMR investigation of crystalline (±)-phendimetrazine bitartarate. The O-CH₂-CH₂-N torsion angle of –58.4(6)° in the solid-state agrees nicely with the 56.0(7)° dihedral angle value estimated by¹H NMR spectroscopy for the major (equatorialN-methyl) phendimetrazine mesylate species in CD₂Cl₂ solution. A common solid-state conformational arrangement was found for (+)-phendimetrazine and a series of six other anorexic drugs structurally analogous to (+)-(2S, 3S)-pseudoephedrine. In this arrangement, NCH(Me)CPh has (S)-configuration, there is a (–)-gaucheMe-CH-C-Ph torsion angle, an antiperiplanarN-CH-C-Ph torsion angle, and the phenyl ring approximately eclipses the C-H bond of the attached carbon (e.g., H-C-C_ipso-C_ortho ca. 4° for 2,3-transphendimetrazine). Nonbonded interactions involving the 3-methyl and the 2-phenyl groups open up the H-C-C_ipso-C_ortho angle in a series of solid-state structures containing the epimeric (–)-(2R, 3S)-ephedrine moiety (e.g., ca. 45° for molecular mechanics calculated 2,3-cis-phendimetrazine model).     

Two new isomeric lignans from <Emphasis Type="Italic">Eusideroxylon zwageri</Emphasis>

Two new lignans were isolated with two other known compounds, eusiderin A and eusiderin I, from Eusideroxylon zwageri (billian). The two new lignans have isomeric structure. The structures of the new lignans were determined to be (2R,3R,4S)-2,3-dimethyl-6,7-dimethoxy-4-ethoxy (3′,4′,5′-trimethoxybenzene)-1,5-dihydroxytetralin and (2R,3S,4S)-2,3-dimethyl-6,7-dimethoxy-4-ethoxy(3′,4′,5′-trimethoxybenzene)-1,5-dihydroxytetralin. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 303–305, May–June, 2009.     

Si-Containing Amides of Phosphoric Acid

The first representative of the N-silylmethylamides of phosphoric acid O=P[NMe(CH₂SiMe _n (OEt)_3-n ]₃ have been synthesized by interaction of MeNHCH₂SiMe _n (OEt)_3-n (n = 2, 3) with POCl₃. The interaction of the N,N′,N″-trimethyl-N,N′,N″-tris[(ethoxydimethyl- silyl)methyl]triamide phosphoric acid with BF₃·Et₂O or BCl₃ results in the formation of the N,N′,N″-trimethyl-N,N′,N″-tris[(fluorodimethyl-silyl)methyl]triamide phosphoric acid or N,N′,N″-trimethyl-N,N′,N″-tris[(chlorodimethylsilyl)methyl]triamide phosphoric acid. NMR data show on the tetracoordinate state of silicon in these products.     

A new cerebrogalactoside from <Emphasis Type="Italic">Juglans mandshurica</Emphasis>

A new cerebrogalactoside, Juglans cerebroside A (1), together with five known compounds, quercetin-3-O-β-D-galactopyranoside (2), myricetin-3-O-β-D-galactopyranoside (3), 2″E-quercetin-3-O-β-D-(6″″-O-[3″(4′″-hydroxyphenyl) propylene acyl]) glucopyranoside (4), gallic acid (5), and 2-methyl-1-hexadecanol (6) were isolated from the leaves of Juglans mandshurica Maxim. The structures of these compounds were determined by 1D, 2D NMR, and MS techniques.     

A new flavanone glucoside from <Emphasis Type="Italic">Abrus precatorius</Emphasis>

A new flavanone glycoside, (2S)5,7,4′-trihydroxyflavanone-8-C-β-D-(6″-O-acetyl)glucopyranoside (1), together with six known flavonoids, isohemiphloin (2), vitexin (3), cirsimaritin (4), hispidulin (5), apigenin (6), and eupatorin (7), was isolated from the leaves and stems of Abrus precatorius. Their structures were elucidated on the basis of physical and spectral analysis. Rotamers exist for compounds 1, 2, and 3. Compounds 1–3, 6, and 7 were isolated from this plant for the first time.     

Synthesis and characterization of 2-phenylaniline cyclopalladated complexes

Reaction of the dinuclear complex [Pd{κ2-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}Cl]₂ (1) with ligands (L = 4-picoline, sym-collidine) gave the six-membered palladacycles [Pd{κ2-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}Cl(L)] (2). The complex 1 reacted with AgX (X = CF₃SO₃, BF₄) and bidentate ligands [L–L = phen (phenanthroline), dppe (bis(diphenylphosphino)ethane), bipy(2,2′-bipyridine) and dppp (bis(diphenylphosphino)propane)] giving the mononuclear orthopalladated complexes [Pd{κ2-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}(L–L)] (3) [L–L = phen, dppe, bipy and dppp]. These compounds were characterized by physico-chemical methods, and the structure of [Pd{κ2-N2′,C1-2-(2′-NH₂C₆H₄)C₆H₄}Cl(L)] (L = sym-collidine) was determined by single-crystal X-ray analysis.