Radical Anions of Polyalkylazulenes: An ESR and ENDOR Study

Proton-hyperfine data are reported for the radical anions generated from azulene ( 1 ) and its alkyl derivatives 2 – 11 in 1,2-dimethoxyethane both ‘chemically’ with K and electrolytically. The alkyl derivatives are 1,3-dimethyl- ( 2 ), 5,7-dimethyl- ( 3 ), 1,3,5,7-tetramethyl- ( 4 ), 2-methyl- ( 5 ), 4,6,8-trimethyl- ( 6 ), 2,4,6,8-tetramethyl-( 7 ), 1,3,4,6,8-pentamethyl- ( 8 ), 1,3,4,8-tetramethyl-6-propyl- ( 9 ), 6-(tert-butyl)-1,3,4,8-tetramethyl- ( 10 ), and 1,2,3,4,6,8-hexamethylazulene ( 11 ). Alkyl substituents at the odd-numbered centers μ = 1, 3, 5, and 7 partly shift the π-spin population from the seven- to the five-membered ring, whereas those at the even-numbered centers μ = 4, 6, and 8 exert an opposite effect on the π-spin distribution.     

Separation of the α-Tocopherol Model Compound 2,2,5,7,8-Pentamethyl-6-Chromanol from its Oxidation Products by High Performance Liquid Chromatography

Abstract

A rapid method is described for the separation of the α-tocopherol model compound, 2,2,5,7,8-pentamethyl-6-chromanol (6), from 9 of its oxidation products in a single 35 minute run. Separated derivatives of 6, in order of elution, included the 5-cholesteroxymethyl (1), spirotrimer (2), spirodimer (3), 5-formyl (4), 5-ethoxymethyl (5), dihydroxydimer (7), chroman dione (8), quinone (9) and pyrano xanthene (10). A normal phase system, using gradient elution is employed, the eluent being monitored at 290 nm. The minimum detection limit for compounds 1–8 was 0.1 μg per injection and for compounds 9 and 10 it was 0.3 μg per injection.     

Indole derivatives

The Fischer condensation of arylhydrazones of 2, 2, 5, 5-tetramethyl-pyrrolid-3-one has given 1, 1, 3, 3-tetramethyl-7, 8-benzo-1, 2, 3, 4-tetrahydropyrrolo[3, 4-b]indole and 1, 1, 3, 3, 7-pentamethyl-1, 2, 3, 4-tetrahydropyrrolo[3, 4-b]indole. On Clemmensen reduction of the latter, the pyrrole ring undergoes degradation.     

Indole derivatives

The Fischer condensation of arylhydrazones of 2, 2, 5, 5-tetramethyl-pyrrolid-3-one has given 1, 1, 3, 3-tetramethyl-7, 8-benzo-1, 2, 3, 4-tetrahydropyrrolo[3, 4-b]indole and 1, 1, 3, 3, 7-pentamethyl-1, 2, 3, 4-tetrahydropyrrolo[3, 4-b]indole. On Clemmensen reduction of the latter, the pyrrole ring undergoes degradation.For Part XXIX, see [1].     

Nebenreaktionen bei der radikalischen,intramolekularen Cycloaddition von 2.6-Bis(2-methacryloyloxy-5-methylbenzyl)-4-methylphenylmethacrylat. Beitrag zu einer Matrizenreaktion

Zusammenfassung Die mit 2-Cyano-2-propylradikalen aus AIBN ausgel?ste und beendete intramolekulare Cycloaddition von 2,6-Bis(2-methacryloyloxy-5-methylbenzyl)-4-methylphenylmethacrylat (1) gibt die Cycloaddukte 4-Methyl-1,2,6-benzoltriyl-2,6-bis(4-methyl-2-methy-len-1,2-phenylen)-2,9-dicyano-2,3,5,7,9-pentamethyl-3, 5,7-dekantricarboxylat (1a) und -2,9-dicyano-2,3,5,8,9-pentamethyl-3,5,8-dekantricarboxylat (1b), welche molekulareinheitliche Leiteroligpmere vorstellen. Daneben bildeten sich 10-(2-Cyano-2-methylpropyl)8-(2-cyano-2-propyl)-4- {2-[(2-cyano-2-methylpropyl) acryloyloxy]-5-methylbenzyl∼-2,8,10,15-tetramethyl-7, 11-dioxo-dibenzo[b,e]-1,7-dioxacyclododekan-2,5-dien (1c) und 6 {2-[4-Cyano-2-(2-cyano-2-propyl)-2,4-dimethylvaleryloxy]-5-methylbenzyl}-4,4′-dimethyl-2,2′-methylendiphenyl-bis[2-(2-cyano-2-methylpropyl) acrylat] (1d). Bezogen auf den Ausgangsester1 konnten insgesamt 92% getrennte und dünnschicht-chromatographisch reine Reaktionsprodukte gefa?t werden. Die den Verbindungen zugeordneten Strukturen wurden mittels IR- und UV-Spektren sowie¹H-NMR- und massenspektrometrische Analyse gesichert. Die Cycloaddukte1a und1b sind Produkte einer synthetischen Matrizenreaktion(7), deren Ergebnisse an anderer Stelle mitgeteilt werden soll.

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Summary The intramolecular cycloaddition of 2,6-bis(2-methacryloyloxy-5-methylbenzyl)-4-methylphenyl-methacrylate (1) was started and terminated by 2-cyano-2-propyl radicals from azoisobutyronitrile. The cycloadducts are 4-methyl-1,2,6-benzoltriyl-2,6-bis (4-methyl-2-methylene-1,2-phenylene)-2,9-dicyano-2,3, 5,7,9-pentamethyl-3,5,7-decanetricarboxylate (1a) and-2,9-dicyano-2,3,5,8,9-pentamethyl-3,5,8-decanetricarboxylate (1b), which are also molecularly uniform ladder oligomers. The side products are e]-1,7-dioxacyclododecane-2,5-diene (1c) and 6{2-[4-cyano-2-(2-cyano-2-propyl)-2,4-dimethylvaleryloxy]-5-methylbenzyl∼-4,4′-dimethyl-2,2′-methylenediphenyl-bis[2-(2-cyano-2 methylpropyl)acrylate] (1d). All together and relative to the starting ester1 92 % thin layer chromatographically pure reaction products could be isolated. The suggested structures of the compounds were confirmed by infrared and ultraviolet spectra as well as by¹H-NMR and mass spectroscopical analysis. The cycloadducts1a and1b are compounds of a matrix reaction (7). Their results will be published elsewhere.

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Mit 3 Abbildungen und 5 Tabellen     

Polyhedral monocarbaborane chemistry. Some C-phenylated seven, eight, nine, ten, eleven and twelve-vertex species

Some synthetic and structural systematics for monocarbaboranes, using the C-phenylated motif as the example, are investigated. The 10-vertex [6-Ph-nido-6-CB(9)H(11)](-) anion 1, from reaction of PhCHO with B(10)H(14) in KOH/H(2)O, is a useful entry synthon into C-phenyl monocarbaborane chemistry. Treatment of anion 1 with Na/thf yields the 10-vertex [1-Ph-closo-1-CB(9)H(9)](-) anion 2a, whereas treatment of anion 1 with iodine in alkaline solution yields the isomeric 10-vertex [2-Ph-closo-2-CB(9)H(9)](-) anion 2b, which isomerises quantitatively to 2a on heating under reflux in DME. Thermolysis of anion 1 yields the 9-vertex [4-Ph-closo-4-CB(8)H(8)](-) anion 5, whereas treatment of anion 1 with FeCl(3)/HCl gives neutral 9-vertex [4-Ph-arachno-4-CB(8)H(13)] 3. Compound 3 gives neutral 9-vertex [1-Ph-nido-1-CB(8)H(11)] 4 in refluxing toluene, and gives the 7-vertex [2-Ph-closo-2-CB(6)H(6)](-) anion 7 and the 8-vertex [1-Ph-closo-1-CB(7)H(7)](-) anion 6 in refluxing toluene with NEt(3). Reaction of 1 with [BH(3)(thf)] yields the 11-vertex [7-Ph-nido-7-CB(10)H(12)](-) anion 8 which can be converted to the 12-vertex [1-Ph-closo-1-CB(11)H(11)](-) anion 10 using [BH(3)(SMe(2))]; alternatively, anion 1 yields anion 10 directly on treatment with [BH(3)(NEt(3))]. Treatment of anion 8 with I(2)/KOH yields the 11-vertex [2-Ph-closo-2-CB(10)H(10)](-) anion 9. The structures of anions 1, 2a, 2b, 5, 6, 7, 8, 9 and 10 have been established by single-crystal X-ray diffraction analyses of their [NEt(4)](+) salts, and those of neutral 3 and 4 estimated by DFT calculations at the B3LYP/6-31G* level; similar calculations have also been applied to the new anionic closo species 2a, 2b, 5, 6, 7, 9 and 10. Crystals of the [NEt(4)](+) salt of the [2-Ph-closo-2-CB(6)H(6)](-) anion 7 required synchrotron X-radiation for sufficient diffraction intensity for molecular-structure elucidation. The syntheses are in principle generally applicable to give extensive derivative C-aryl and C-alkyl chemistries.     

无外加催化剂条件下邻取代芳香醛与5, 5-二甲基-1, 3-环己二 酮的反应研究

在DMF溶剂中,不外加催化剂使邻取代芳香醛(1)与5,5-二甲基-1,3-环己二酮(2)发生缩合和加成反应生成3,3,6,6-四甲基-4a-羟基-9-芳基-1,8-二氧代-2,3,4,4a,5,6,7,8,9,9a-十氢化-1H-氧杂蒽(3a-3d)。在同样条件下,邻羟基芳香醛与5,5-二甲基-1,3-环己二酮则发生缩合、加成和脱水反应生成3,3-二甲基-9-(5,5-二甲基-3-羟基-2-环己烯-1-酮-2-基)-1-氧代-2,3,4,9-四氢化-1-氧杂蒽(4a-4b)。用单晶X-射线分析法确定了产物3a和4a的晶体结构。     

The mass spectrum of 1:12, 2:3, 4:5, 6:7, 8:9, 10:11-hexabenzocoronene

The mass-spectra of 1:12, 2:3, 4:5, 6:7, 8:9, 10:11-hexabenzocoronene and the isomer 1:2, 3:4, 5:6, 7:8, 9:10, 11:12-hexabenzocoronene have been examined. The former is typically that of an aromatic conjugated hydrocarbon and is sparse, the latter is more intense. It is conjectured that the former may be found in interstellar space.     

Remarkable effect of water on functionalization of the phenyl ring in methyl-substituted benzene derivatives with F-TEDA-BF4

Various N-F reagents reacted with hexamethylbenzene (1) forming side chain substituted alkoxides or esters in protic solvents, Ritter type side chain functionalization was observed in acetonitrile in the presence of trifluoroacetic acid, while in aqueous acetonitrile solution phenyl ring transformation took place, starting with ipso attack of water and further rearrangement of the methyl group as the main process. Rearranged 2,3,4,5,6,6-hexamethylcyclohexa-2,4-dienone (7) was transformed to 5-fluoro-2,3,5,6,6-pentamethyl-4-methylenecyclohex-2-en-1-one (8) or 5-hydroxy-2,3,5,6,6-pentamethyl-4-methylenecyclohex-2-en-1-one (9). 1,2,3,4,5,6-Hexamethyl-bicyclo[2.2.0]hexa-2,5-diene reacted with F-TEDA-BF4 in the presence of water and 7 was formed in high yield. Durene (12) followed similar ipso attack of water as 1, but on the other hand 1,2,3,4-tetramethylbenzene displayed different regioselectivity and 2,3,4,5-tetramethylphenol was formed, further transforming to 4-fluoro-2,3,4,5-tetramethylcyclohexa-2,5-dienone. The functionalizations of methylbenzenes obeyed a second-order rate equation v = d[N-F]/dt = k2[N-F][substrate], and DeltaG# values between 77 and 94 kJ/mol were determined. The presence of water did not significantly influence DeltaG# but considerably affected DeltaS# and positive values were found where methyl group migration was the dominant process (9.1 J/(mol K) for 1 and 0.5 J/(mol K) for 12). A higher reactivity of durene than mesitylene (k2(MES)/k2(DUR) = 0.23) was found, supporting the assumption that single electron transfer (SET) is the dominant process in the functionalizations of methyl-substituted benzene derivatives with F-TEDA-BF4.     

Synthesis, structure, and magnetic properties of (6-9)-nuclear Ni(II) trimethylacetates and their heterospin complexes with nitroxides

New polynuclear nickel trimethylacetates [Ni6(OH)4(C5H9O2)8(C5H10O2)4] (6), [Ni7(OH)7(C5H9O2)7(C5H10O2)6(H2O)] x 0.5 C6H14 x 0.5 H2O (7), [Ni8(OH)4(H2O)2(C5H9O2)12] (8), and [Ni9(OH)6(C5H9O2)12(C5H10O2)4] x C5H10O2 x 3 H2O (9), where C5H9O2 is trimethylacetate and C5H10O2 is trimethylacetic acid, have been found. Their structures were determined by X-ray crystallography. Because of their high solubility in low-polarity organic solvents, compounds 6-9 reacted with stable organic radicals to form the first heterospin compounds based on polynuclear Ni(II) trimethylacetate and nitronyl nitroxides containing pyrazole (L(1)-L(3)), methyl (L(4)), or imidazole (L(5)) substituent groups, respectively, in side chain [Ni7(OH)5(C5H9O2)9(C5H10O2)2(L(1))2(H2O)] x 0.5 C6H14 x H2O (6+1a), [Ni7(OH)5(C5H9O2)9(C5H10O2)2(L2)2(H2O)] x H2O (6+1b), [Ni7(OH)5(C5H9O2)9(C5H10O2)2(L(3))2(H2O)] x H2O (6+1c), [Ni6(OH)3(C5H9O2)9(C5H10O2)4(L(4))] x 1.5 C6H14 (6'), and [Ni4OH)3(C5H9O2)5(C5H10O2)4(L(5))] x 1.5 C7H8 (4). Their structures were also determined by X-ray crystallography. Although Ni(II) trimethylacetates may have varying nuclearity and can change their nuclearity during recrystallization or interactions with nitroxides, this family of compounds is easy to study because of its topological relationship. For any of these complexes, the polynuclear framework may be derived from the [Ni6] polynuclear fragment {Ni6(mu4-OH)2(mu3-OH)2(mu2-C5H9O2-O,O')6(mu2-C5H9O2-O,O)(mu4-C5H9O2-O,O,O',O')(C5H10O2)4}, which is shaped like an open book. On the basis of this fragment, the structure of 7-nuclear compounds (7 and 6+1a-c) is conveniently represented as the result of symmetric addition of other mononuclear fragments to the four Ni(II) ions lying at the vertexes of the [Ni6] open book. The 9-nuclear complex is formed by the addition of trinuclear fragments to two Ni(II) ions lying on one of the lateral edges of the [Ni6] open book. This wing of the 9-nuclear complex preserves its structure in another type of 6-nuclear complex (6') with the boat configuration. If, however, two edge-sharing Ni(II) ions are removed from [Ni6] (one of these lies at a vertex of the open book and the other, on the book-cover line), we obtain a 4-nuclear fragment recorded in the molecular structure of 4. Twinning of this 4-nuclear fragment forms highly symmetric molecule 8, which is a new chemical version of cubane.     

Synthesis,Anti‐Microbial,and Cytotoxic Activities Evaluation of Some New Pyrido[2,3‐d]Pyrimidines

Novel pyridine derivatives 1d and 7 , pyrido[2,3‐d]pyrimidine derivatives 2a , 2b , 2c , 2d , 3a , 3b , 3c , 3d , 4a , 4b , 4c , 4d , 5a , 5b , 5c , 5d , 6a , 6b , 6c , 6d , 8a , 8b , and 9a , 9b were synthesized and screened for their anti‐microbial and cytotoxic activities. Compounds 2b , 2c , 3b , 3c , 5b , 5c , 6b , 6c , and 7 showed excellent anti‐microbial activities against all the tested bacteria and fungi compared to the reference drugs. Furthermore, they exhibited high safety profile in cytotoxicity test except 2c and 3c . The structures of the newly synthesized compounds were confirmed by spectral data and elemental analysis.     

Synthesis of 1,8- and 2,8-dihydrocycloheptapyrazol-8-one derivatives by the reactions of 3-acetyltropolone and its methyl ethers with phenylhydrazine

3-Acetyltropolone ( 1 ) reacted with phenylhydrazine to give 3-acetyltropolone phenylhydrazone ( 3 ) and 3-methyl-1-phenyl-1,8-dihydrocycloheptapyrazol-8-one ( 4 ). The former ( 3 ) cyclized to afford the latter ( 4 ). The reaction of 3-acetyl-2-methoxytropone ( 2a ) with phenylhydrazine gave 4 , 3-methyl-2-phenyl-2,8-dihydrocyclo-heptapyrazol-8-one ( 5 ), and 3-methyl-2-phenyl-2,8-dihydrocycloheptapyrazol-8-one phenylhydrazone ( 6 ). The compound ( 5 ) reacted with phenylhydrazine to afford 6 . The reaction of 7-acetyl-2-methoxytropone ( 2b ) with phenylhydrazone gave 7-acetyl-2-methoxytropone phenylhydrazone ( 7 ), 7-acetyl-2-(N′-phenylhydrazino)-tropone phenylhydrazone ( 8 ), 3-methyl-1-phenyl-1,8-dihydrocycloheptapyrazol-8-one phenylhydrazone ( 9 ), and 6 . The compound ( 7 ) was heated to afford 4 and reacted with phenylhydrazine to afford 8 and 9 . The compound ( 8 ) was also refluxed to give 9 .     

Synthesis, characterization, and substitution chemistry of [Bu4N]2[W6Cl8(OSO2CF3)6]. A versatile precursor for axially substituted clusters containing the (W6Cl8)4+ core

The new cluster [Bu4N]2[W6Cl8(OSO2CF3)6] (1) has been prepared and structurally characterized. This material is an effective precursor for the generation of cluster ions with the general formula [W6C18L6]n (L = Cl-, Br-, I-, NCS-, NCO-, NCSe-, and O=PPh3; n = 2- or 4+). The last three clusters are new. The products have been characterized by IR spectroscopy, NMR spectroscopy, and FAB mass spectrometry. In addition to 1, the products [Bu4N]2[W6C18(NCS)6] (5) and [Bu4N]2[W6C18(NCO)6] (7) were structurally characterized. Crystal data for 1: space group, P2(1/c) (No. 14); a = 11.116(5) A; b = 27.952(1) A; c = 24.516(1) A; beta = 95.182(9) degrees; V = 7586.3(5) A3; Z = 4. Crystal data for 5: space group, P2(1/n) (No. 14); a = 11.3323(9) A; b = 12.3404(9) A; c = 44.583(3) A; beta = 97.089(1) degrees ; V = 6187.1(7) A3; Z = 4. Crystal data for 7: space group, P1 (No. 2); a = 11.8009(8) A; b = 11.9332(8) A; c = 11.9522(8) A; alpha = 77.904(1) degrees; beta = 95.182(9) degrees; gamma = 62.574(1) degrees V = 1450.5(2) A3; Z = 1.     

Novel dimetal bridging carbene complexes derived from a terminal carbonyl dimetal compound. Syntheses, structures and reactivities of 7H-indene-coordinated diiron bridging carbene complexes

Pentacarbonyl-7H-indenediiron, [Fe2(CO)5(eta3,eta5-C9H8)] (1), reacts with aryllithium, ArLi (Ar = C6H5, p-C6H5C6H4), followed by alkylation with Et3OBF4 to give novel 7H-indene-coordinated diiron bridging alkoxycarbene complexes [Fe2{mu-C(OC2H5)Ar}(CO)4(eta4,eta4-C9H8)] (2, Ar = C6H5; 3, Ar = p-C6H5C6H4). Complexes 2 and 3 react with HBF4.Et2O at low temperature to yield cationic bridging carbyne complexes [Fe2(mu-CAr)(CO)4(eta4,eta4-C9H8)]BF4 (4, Ar = C6H5; 5, Ar = p-C6H5C6H4). Cationic 4 and 5 react with NaBH4 in THF at low temperature to afford diiron bridging arylcarbene complexes [Fe2{mu-C(H)Ar}(CO)4(eta4,eta4-C9H8)] (6, Ar = C6H5; 7, Ar = p-C6H5C6H4). The similar reactions of 4 and 5 with NaSC6H4CH3-p produce the bridging arylthiocarbene complexes [Fe2{mu-C(Ar)SC6H4CH3-p}(CO)4(eta4,eta4-C9H8)] (8, Ar = C6H5; 9, Ar = p-C6H5C6H4). Cationic 4 and 5 can also react with anionic carbonylmetal compounds Na[M(CO)5(CN)] (M = Cr, Mo, W) to give the diiron bridging aryl(pentacarbonylcyanometal)carbene complexes [Fe2{mu-C(Ar)NCM(CO)5}(CO)4(eta4,eta4-C9H8)] (10, Ar = C6H5, M = Cr; 11, Ar = p-C6H5C6H4, M = Cr; 12, Ar = C6H5, M = Mo; 13, Ar = p-C6H5C6H4, M = Mo; 14, Ar = C6H5, M = W; 15, Ar = p-C6H5C6H4, M = W). Interestingly, in CH2Cl2 solution at room temperature complexes 10-15 were transformed into the isomerized 7H-indene-coordinated monoiron complexes [Fe(CO)2(eta5-C9H8)C(Ar)NCM(CO)5] (16, Ar = C6H5, M = Cr; 17, Ar = p-C6H5C6H4, M = Cr; 18, Ar = C6H5, M = Mo; 19, Ar = p-C6H5C6H4, M = Mo; 20, Ar = C6H5, M = W; 21, Ar = p-C6H5C6H4, M = W), while complex 3 was converted into a novel ring addition product [Fe2{C(OC2H5)C6H4C6H5-p-(eta2,eta5-C9H8)}(CO)5] (22) under the same conditions. The structures of complexes 2, 6, 8, 14, 18 and 22 have been established by X-ray diffraction studies.     

Self-assembly, structures, and photophysical properties of 4,4'-bipyrazolate-linked metallo-macrocycles with dimetal clips

By employing functional diimine ligands coordinated dipalladium(II,II) or diplatinum(II,II) clips as corners and the coplanar 4,4'-bipyrazolate dianion (L(2-)) ligand as linker, a series of bipyrazolate-bridged metallo-macrocycles, namely, [M8L4](NO3)8 (M = Pd(dmbpy), 1; Pd(bpy), 2; Pt(bpy), 3a; Pd(phen), 4; Pt(phen), 5; Pd(15-crown-5-phen), 6; Pd(18-crown-6-phen), 8; Pd(benzo-24-crown-8-phen), 10a; Pt(15-crown-5-phen), 7a, Pt(18-crown-6-phen), 9a; Pt(benzo-24-crown-8-phen), 11a) and [M6L3](NO3)6 (M = Pt(bpy), 3b; Pt(15-crown-5-phen), 7b; Pt(18-crown-6-phen), 9b; Pd(benzo-24-crown-8-phen), 10b; Pt(benzo-24-crown-8-phen), 11b), have been synthesized through a directed self-assembly approach that involves spontaneous deprotonation of the 1H-bipyrazolyl ligands in aqueous solution. All these compounds have a crown-shaped cavity that can serve as host to solvent molecules and anions. The structures are characterized by elemental analysis, (1)H and (13)C NMR, ESI-MS, and in the cases of 1a (the BF4(-) salt of 1), 2a (the BF4(-) salt of 2), and 3b by single-crystal X-ray diffraction analysis. Photophysical properties for complexes 1 and 2 are discussed.     

Synthesis,Antiviral, and Antimicrobial Activity of N‐ and S‐Alkylated Phthalazine Derivatives

A series of N‐alkylphthalazinone were synthesized by the reaction of phthalazin‐1(2H)‐one derivatives 1a , 1b , 1c with alkylating agents namely, propargyl, allyl bromide, epichlorohydrin, 1,3‐dichloro‐2‐propanol, 4‐bromobutylacetate, and 1‐(bromomethoxy)ethyl acetate to give the corresponding N‐alkylphthalazinone 2a , 2b , 2c , 3a , 3b , 3c , 5a , 5b , 5c , 6a , 6b , 6c , 7a , 7b , 7c , and 9a , 9b , 9c . Alkylation of phthalazin‐1(2H)‐thione to give a series from S‐alkylphthalazine 12 , 13 , 14 and thioglycosides 15 and 17 was performed. Deprotection of compounds 7a , 7b , 7c , 9a , 9b , 9c , 15 , and 17 resulted in the formation of the corresponding products 8a , 8b , 8c , 10a , 10b , 10c , 16 , and 18 . The structure of newly synthesized compounds was assigned by IR, ¹H, ¹³C NMR, and elemental analysis. Some of these compounds were screened for antiviral and antimicrobial activity.     

Chemoenzymatic synthesis of (+)-totarol, (+)-podototarin, (+)-sempervirol, and (+)-jolkinolides E and D

The enzymatic resolution products [(1R,4aR,8aR)-1,2,3,4,4a,5,6,7,8,8a-decahydro-5,5,8a-trimethyl-2-oxo-trans-naphthalene-1-methanol-2-ethylene acetal (8aR)-7 (98% ee) and {acetate of (1S,4aS,8aS)-1,2,3,4,4a,5,6,7,8,8a-decahydro-5,5,8a-trimethyl-2-oxo-trans-naphthalene-1-methanol-2-ethylene acetal} (8aS)-9 (>99% ee)] obtained by the lipase-catalyzed enantioselective acetylation of (±)-7 in the presence of vinyl acetate as an acyl donor were converted to the ,β-unsaturated ketones (8aR)-6 and (8aS)-6, respectively. Concise syntheses of (+)-totarol 1, (+)-podototarin 2 and (+)-sempervirol 3 were achieved based on Michael reactions between (8aS)-6 and the appropriate β-keto ester followed by aldol condensation. The first chiral syntheses of (+)-jolkinolides E 4 and D 5 were achieved from (5R,10R,12R)-12-hydroxypodocarpa-8(14)-en-13-one 15 derived from (8aR)-6.     

Donor-Free Alkali Metal Thiolates: Synthesis and Structure of Dimeric, Trimeric, and Tetrameric Complexes with Sterically Encumbered Terphenyl Substituents

The synthesis and characterization of the tetrameric lithium thiolate (LiSC(6)H(2)-2,4,6-Ph(3))(4).C(7)H(8) (1), the trimeric lithium thiolate (LiSC(6)H(3)-2,6-Mes(2))(3).C(6)H(14)()()(2) (Mes = 2,4,6-Me(3)C(6)H(2)), the thiol HSC(6)H(3)-2,6-Trip(2) (3) (Trip = 2,4,6-i-Pr(3)C(6)H(2)), and the complete alkali metal series of dimeric thiolates (MSC(6)H(3)-2,6-Trip(2))(2) (M = Li (4, 5), Na (6), K (7), Rb (8), Cs (9)) are described. The compounds were characterized by (1)H, (7)Li, and (13)C NMR and IR spectroscopy and by X-ray crystallography. The compounds 1 and 2 crystallize as four- and three-rung ladder framework structures. The compounds 4-9 crystallize as dimers with M(2)S(2) cores. In addition, the metal ions interact with the ortho aryl groups to varying degrees in all the structures. The extent of these interactions appears to be determined mainly by ionic sizes and geometric factors. The coordination geometry of the thiolato sulfurs also varies from pyramidal in 1, 2, 4, 5, and 6 and one planar and one slightly pyramidal sulfur geometry in 7 to both sulfurs being planar coordinated in 8 and 9. Crystal data at 130 K are as follows: (LiSC(6)H(2)-2,4,6-Ph(3))(4).C(7)H(8) (1), a = 15.961(2) ?, b = 16.243(3) ?, c = 17.114(3) ?, alpha = 89.375(14) degrees, beta = 85.334(14) degrees, gamma = 63.343(12) degrees, V = 3950(1) ?(3), space group P&onemacr;, Z = 2, R(1) = 0.082; (LiSC(6)H(3)-2,6-Mes(2))(3).C(6)H(14)()()(2), a = 14.554(4) ?, b = 14.010(4) ?, c = 32.832(8) ?, beta = 95.20(2) degrees, V = 6667(2) ?(3), space group P2(1)/n, Z = 4, R(1) = 0.089; HSC(6)H(3)-2,6-Trip(2) (3), a = 8.180(2) ?, b = 25.437(5) ?, c = 15.752(3) ?, V = 3278(1) ?(3), space group Pnma, Z = 4, R(1) = 0.045; (LiC(6)H(3)-2,6-Trip(2))(2) (4), a = 12.652(2) ?, b = 14.218(1) ?, c = 18.713(2) ?, alpha = 83.56(1) degrees, beta = 84.36(1) degrees, gamma = 73.82(1) degrees, V = 3205(1) ?(3), space group P&onemacr;, Z = 2, R(1) = 0.055; (LiC(6)H(3)-2,6-Trip(2))(2).C(7)H(8) (5), a = 15.383(3) ?, b = 14.381(2) ?, c = 16.524(2) ?, beta = 111.10(1), V = 3410.3(9) ?(3), space group P2(1)/n, Z = 2, R(1) = 0.086; (NaSC(6)H(3)-2,6-Trip(2))(2).0.5C(7)H(8) (6), a = 13.952(2) ?, b = 20.267(2) ?, c = 24.475(3) ?, beta = 98.673(9) degrees, V = 6842(1) ?(3), space group P2(1)/n, Z = 4, R(1) = 0.068; (KSC(6)H(3)-2,6-Trip(2))(2).C(7)H(8) (7), a = 13.683(4) ?, b = 15.071(4) ?, c = 17.824(5) ?, alpha = 82.73(2), beta = 86.09(2), gamma = 88.46(2), V = 3637(2) ?(3), space group P&onemacr;, Z = 2, R(1) = 0.072; (RbSC(6)H(3)-2,6-Trip(2))(2).C(7)H(8) (8), a = 19.710(3) ?, b = 20.892(3) ?, c = 18.755(2) ?, beta = 106.900(9) degrees, V = 7389(2) ?(3), space group P2(1)/n, Z = 4, R(1) = 0.069; (CsSC(6)H(3)-2,6-Trip(2))(2) (9), a = 13.109(3) ?, b = 15.941(3) ?, c = 17.748(4) ?, alpha = 101.65(2) degrees, beta = 100.76(2) degrees, gamma = 104.25(2) degrees, V = 3410(1) ?(3), space group P&onemacr;, Z = 2, R(1) = 0.048.     

Synthesis and Antimicrobial Studies of Novel Imidazole Containing Bisazetidinones and Bisthiazolidinone Derivatives

A simple, practical, and efficient approach to new series of imidazole containing bisazetidinones ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j and 9a , 9b , 9c , 9d , 9e , 9f , 9g , 9h , 9i , 9j ) was prepared by Staudinger [2 + 2] cycloaddition reaction, and bisthiazolidinones ( 8a , 8b , 8c , 8d , 8e , 8f , 8g , 8h , 8i , 8j and 10a , 10b , 10c , 10d , 10e , 10f , 10g , 10h , 10i , 10j ) were obtained by cyclization of bisimines with thioglycolic acid. The bisimines ( 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j and 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j ) were synthesized by the condensation of 3‐(1‐(3‐aminobenzyl)‐4, 5‐dihydro‐1H‐imidazol‐2‐yl) aniline ( 3 , 4 ) with a series of different substituted aromatic aldehydes. All the newly synthesized target compounds were evaluated for their in vitro antimicrobial activity against two Gram‐positive bacteria and two Gram‐negative bacteria. Additionally, these synthesized compounds were tested for their antifungal activities. Few compounds showed very good antibacterial and antifungal activity.     

Polynuclear heterocyclic compounds. XIX. Reduction of 3,3,6,6-tetramethyloctahydroacridine-1,8-diones

Reduction in alcohol solution, using hydrogen at atmospheric pressure and platinum oxide catalyst, of 3, 3, -6, 6-tetramethyl-1, 2, 3, 4, 5, 6, 7, 8-octahydroacridine-1, 8-dione and its 9-phenyl derivative gives the corresponding 3, 3, 6, 6-tetramethyl-1, 2, 3, 4, 5, 6, 7, 8, 9, 10-decahydroacridine-1, 8-dione and its 9-phenyl derivative.For part XVIII see [1].