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The presence of a self-replicator in a dynamic combinatorial library (DCL) offers function above and beyond libraries under thermodynamic control, moving towards out-of-equilibrium systems which mimic biological networks. In this work, we examine a previously reported DCL based on reversible imine formation to give amphiphilic structures. The amphiphilic imines were readily produced in organic solvents, and were found to aggregate to micelles in water as judged by diffusion-ordered NMR spectroscopy, dynamic light scattering and interferometric scattering microscopy. Unfortunately, the autocatalytic formation of products was not observed in water, and preformed imines slowly hydrolysed to aldehyde and amine components at neutral pD. [ABSTRACT FROM AUTHOR]

Several planar chiral [2.2]paracyclophane-based phosphine-phenol catalysts were prepared and applied to the aza-Morita-Baylis-Hillman reaction of aldimines with vinyl ketones. The pseudo-ortho- substituted aryl[2.2]paracyclophanol, in which the phosphino group was located at the meta -position of the aryl group, showed an exceptionally high reactivity and good enantioselectivity for the reaction of N -tosylated aldimines with various alkyl or aryl vinyl ketones. [ABSTRACT FROM AUTHOR]

Rare nonaromatic 3 H -pyrroles have been synthesized from ketoximes having only one C–H bond adjacent to the oxime function and acetylene under pressure (10–13 atm) at 70 °C in two-phase superbase media of KOH/DMSO/ n -hexane type, the yields ranging 8–36%. The effect of substituents, superbase nature and reaction conditions on yields of the target 3 H -pyrroles has been analyzed. Hydroxypyrroline/3 H -pyrroles interconversion as well as relative stability of model 3 H -pyrroles have been assessed quantum chemically (MP2/6-31++G**//B3LYP/6-31G**). [ABSTRACT FROM AUTHOR]

Two new highly oxygenated hexacyclic cyclopiazonic acid (CPA) alkaloids, speradines B and C ( 1 and 2 ), together with one new related tetracyclic oxindole alkaloid, speradine D ( 3 ), were isolated from the sponge derived fungus Aspergillus flavus MXH-X104. Among them, speradine C ( 2 ) possesses unprecedented 6/5/6/5/5/6 hexacyclic ring system and 4-oxo-1, 3-oxazinane ring. The structures including absolute configurations of 1 – 3 were deduced from the spectroscopic data, X-ray diffraction analysis and the computational method including the calculation of the chemical shifts and the electronic circular dichroism (ECD) spectra. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and rapid procedure for ring opening reaction of various epoxides with phenol and thiophenol derivatives was developed. The procedure can be obtained at room temperature under solvent-free condition in presence of (C4H12N2)2[BiCl6]Cl·H2O (1 mol %). This catalyst can be reused several times without significant loss of activity. [Copyright &y& Elsevier]

Abstract: Seven novel bis-N-substituted-hydrazinecarboxamide receptors were synthesized in good to excellent yields by reacting chiral dicarbohydrazides, obtained from commercially available tartaric acid, with substituted aromatic isocyanates. The newly synthesized hydrazinecarboxamides formed structurally unique supramolecular aggregates, which have been confirmed by ESI-TOF/MS and tandem ESI-MS. They also showed molecular recognition to a selection of chiral carboxylic guests and oligopeptides, which mimic the backbone structure of the bacterial cell wall. The structures of the novel compounds were verified by various spectroscopic techniques including FTIR, 1H NMR, 13C NMR, ESI-TOF/MS, tandem ESI-MS, 2D ROESY NMR, and CD spectroscopy. [Copyright &y& Elsevier]

Abstract: NIS/NaN3 mediated ring opening of various donor–acceptor cyclopropanes has been investigated. The study shows the necessity of the donor oxygen lone pair in such ring opening reactions. This methodology has been utilized in the synthesis of C-1 linked pseudodisaccharides through the use of click chemistry. [Copyright &y& Elsevier]

Abstract: A novel family of nitrogen stilbene analogs, 1-styrylpyrroles, has been synthesized in good to excellent yields by a straightforward facile transition metal-free addition of pyrroles to arylacetylenes in the KOH/DMSO system (90–120°C, 5–13h). Thermodynamically controlled E/Z-isomer ratio of 1-styrylpyrroles depends on structure of both pyrroles and acetylenes ranging from ca. 100% E-stereoselectivity (for the pair unsubstituted pyrrole—phenylacetylene) to 90, 96% Z-stereoselectivity (for the pairs: 2-phenylpyrrole—phenylacetylene and 2-(2-thienyl)pyrrole—phenylacetylene, respectively). [Copyright &y& Elsevier]

Abstract: The synthesis of 4-isoxazolines via 1,3-dipolar cycloaddition of nitrones generated from allenoates and the subsequent thermal rearrangement to pyrroles is reported. The selection of the reaction conditions allowed the isolation of the initial 1,3-dipolar cycloadducts, the 4-isoxazolines, or the pyrrole derivatives. The isomerization of the parent system (4-isoxazoline) was examined by carrying out quantum chemical calculations and corroborated the favourability of the 4-isoxazoline rearrangement to five-membered heterocycles via 2-acylaziridine intermediates. [Copyright &y& Elsevier]

Abstract: Six new humantenine-type (1–6) and two new gelsemine-type (7, 8) oxindole alkaloids and one new indole alkaloid (9) were isolated from the leaves and branches of Gelsemium rankinii. The structures of the new alkaloids were determined by spectroscopic analyses. Among them, 6-hydroxyhumantenine (5) is the first example of a Gelsemium alkaloid with an oxygen function at C-6 position, and is a plausible biogenetic precursor of gelsemine-type alkaloids. [Copyright &y& Elsevier]

Abstract: Site-selective direct arylation of both sp2 and sp3 sites on azine N-oxide substrates is described. The arylation reactions are carried out in either a divergent manner or a sequential manner. The sp3 arylation reaction is applied to the synthesis of the natural products, papaverine and crykonisine, and a rationale for low reactivity of electron-deficient aryl halides is provided. Mechanistic investigations point toward the intimate involvement of the base in the mechanism of these reactions. [Copyright &y& Elsevier]

Abstract: Two new bromopyrrole alkaloids, nagelamides M (1) and N (2), have been isolated from an Okinawan marine sponge Agelas species, and the structures and stereochemistry were elucidated from the spectroscopic data. Nagelamide M (1) is a novel bromopyrrole alkaloid possessing a 2-amino-octahydropyrrolo[2,3-d]imidazole ring with a taurine unit, while nagelamide N (2) is a new bromopyrrole alkaloid possessing a 2-amino-tetrahydroimidazole-4-one ring with a taurine unit and 3-(dibromopyrrole-2-carboxamido)propanoic acid moiety. Nagelamides M (1) and N (2) exhibited antimicrobial activity. [Copyright &y& Elsevier]

Abstract: A new and versatile ‘Pd’/CuI catalyzed protocol was developed for the synthesis in good to high yields of substituted pyrroles from N-Boc-β-iododehydroamino acid methyl esters and several terminal alkynes. This one-pot, two-step procedure occurs by a Sonogashira coupling followed by a 5-endo-dig-cyclization, which involves the nitrogen atom of the dehydroamino acid. After several experiments using different Pd(0) and Pd(II) species it was possible to establish the more general reaction conditions, which are: the use of a Pd(II) catalyst, CuI and Cs2CO3 as base in dry DMF at 70°C. The best yields were obtained with arylacetylenes bearing electron-donating groups and with electron-rich heteroarylacetylenes. [Copyright &y& Elsevier]

Abstract: In the presence of catalytic amount of Cu(OTf)2/trisoxazoline, an enantioselective Friedel–Crafts reaction of N-methyl pyrrole with alkylidene malonates has been developed and up to 66% ee is achieved. [Copyright &y& Elsevier]

Abstract: The synthesis of substituted 2,3-dihydro-1,4-thiazines, fused cycloalkyl-1,4-thiazines, 1,4-benzothiazines and fused cycloalkyl-1,4-benzothiazines by 1,4-addition of 1,2-aminothiols to 1,2-diaza-1,3-dienes bearing carboxylate, carboxamide, or phosphorylated groups and subsequent internal heterocyclization is described. The reaction of carboxylated 1,2-diaza-1,3-butadienes with 2-(butylamino)ethanethiol affords 1,4-thiazinan-3-ones. The solid-phase reaction of polymer-bound 1,2-diaza-1,3-butadienes with 1,2-aminothiols produces 2,3-dihydro-1,4-thiazines and 1,4-benzothiazines. [Copyright &y& Elsevier]

Abstract: Unexpected spiro cyclic products were formed from the reaction of imines and salicylaldehyde with silyl enol ethers in the presence of BF3·OEt2. Different kinds of dioxaspiro products were afforded depending on the nature of starting materials. Furthermore, salicylaldehyde could also react directly with several silyl enol ethers, giving three products with different spiro cyclic structure under the same reaction conditions. [Copyright &y& Elsevier]

Abstract: Two redox anion receptors based on calix[4]pyrrole and ferrocene have been synthesized. The electrochemical investigation revealed that these compounds can be response to the anions with different shifts of Fc/Fc+ couple. With the 1H NMR titration study, the selectivity to F− and AcO− ions in CD3CN solution was confirmed. The conformations of the mono-aromatic meso-substituted calix[4]pyrroles, which were the synthetical intermediate of the ferrocene based receptors, and their anion complexes in the solid state have also been studied by single X-ray crystallography, and the rationality of the crystal conformations was proved by theoretical study. [Copyright &y& Elsevier]

Abstract: A one-pot method for the preparation of 1,2-substituted dihydroquinolines is described. This method features the C-2 addition of a range of organolithium reagents to quinoline followed by the in-situ addition of an electrophile. Standard palladium-catalysed hydrogenation, of the resultant 1,2-disubstituted dihydroquinoline adducts, generates the corresponding 1,2-disubstituted tetrahydroquinoline. A series of such compounds have been synthesised including the natural products; (±)-angustureine 1, cuspareine 2 and galipinine 3. [Copyright &y& Elsevier]

Abstract: Four new gelsedine-type oxindole alkaloids (1–4) were isolated from the leaves and branches of Gelsemium elegans, together with 10 known alkaloids. The structures of the new alkaloids were determined by spectroscopic analyses and partial synthesis from known compounds. Gelsecrotonidine (1), 14-hydroxygelsecrotonidine (2), and 11-methoxygelsecrotonidine (3) possess an additional C2 unit with an acetic acid residue compared to gelsenicine-related monoterpenoid indole alkaloids. 14-Hydroxygelsedilam (4) is an 18,19-nor-type monoterpenoid indole alkaloid. [Copyright &y& Elsevier]

Abstract: Two new types of pyrido-fused tris-heterocycles (1a,b and 2a,b) have been prepared from 3-aminopyridine in five/six steps. A synthetic strategy for the preparation of the novel pyrido[3,4-b]thieno[2,3- and 3,2-d]pyrroles (1a,b) and pyrido[4,3-e]thieno[2,3- and 3,2-c]pyridazines (2a,b) has been studied. The Suzuki cross coupling of the appropriate 2- and 3-thienoboronic acids (3,4) and 4-bromo-3-pyridylpivaloylamide (9) afforded the biaryl coupling products (10,11) in high yields (85%). Diazotization of the hydrolysed (2-thienyl)-coupling product (12) and azide substitution gave the 3-azido-4-(2-thienyl)pyridine intermediate (72%, 14). 3-Azido-4-(3-thienyl)pyridine (15) was prepared by exchanging the previous order of reactions. The desired β-carboline thiophene analogues (1a,b) were obtained via the nitrene by thermal decomposition of the azido precursors (14,15). By optimising conditions for intramolecular diazocoupling, the corresponding pyridazine products (72–83%, 2a,b) were afforded. [Copyright &y& Elsevier]

Abstract: Iron(III) chloride has been used to prepare polymethoxy-substituted phenanthrene-9-carboxylic acid via intramolecular oxidative coupling at room temperature in excellent yields. Mild reaction conditions and the use of environmentally friendly FeCl3 provide a novel practical route for the synthesis of the important phenanthrene ring. The further application of this protocol as the key step to total synthesis of tylophorine, deoxytylophorinine, and antofine was achieved starting from readily available pyrrole in 48%, 44%, and 46% overall yields, respectively. This new and efficient strategy enjoys a number of advantages. The experimental procedure is simple under mild conditions, atom economy is very high without any protecting-group, starting materials are cheap or easily prepared. Hence this short and practical method is applicable to large-scale production. [Copyright &y& Elsevier]

Abstract: Diastereoselective introduction of nucleophiles into l-proline derivatives at the 5-position was achieved with suitable selection of N-protecting group. N-Methoxycarbonylated or benzyloxycarbonylated l-proline derivatives reacted with arene to give cis-arylated products. On the other hand, N-benzoylated l-proline derivative preferentially gave trans-arylated product, which could be easily transformed into optically active C 2-symmetrical pyrrolidine derivative. Such derivative 5 worked well as an organic activator in the asymmetric reduction of aromatic imines by Cl3SiH. [Copyright &y& Elsevier]

Abstract: The 1,3-dipolar cycloaddition reactions of various N-tethered alkenyl aldehydes with some cyclic and acyclic amino acids have been studied. Some key sulfonamides having strategically positioned aldehyde and olefinic tether have been synthesized and effectively subjected to intramolecular azomethine ylide cycloaddition reaction resulting in a series of pyrrolo[3,4-b]pyrrole and its N-1–C-2 derivatives, and a series of novel heterotricyclic compounds, perhydrothiazolo[3′,4′-2,3]pyrrolo[4,5-c]pyrroles, in good yields. The intramolecular cycloaddition reaction was found to be highly stereoselective to form only cis-fused cycloadducts in all cases. [Copyright &y& Elsevier]

Abstract: A new rhodium-based catalytic system for the direct C–H coupling of arenes and iodoarenes that shows high activity with reasonably broad scope was developed. Under the catalytic influence of RhCl(CO){P[OCH(CF3)2]3}2 and Ag2CO3, the direct C–H arylation of heteroarenes and arenes took place with iodoarenes to afford a range of biaryls in good to excellent yields with high regioselectivity. Thiophenes, furans, pyrroles, indoles, and alkoxybenzenes are applicable to this arylation protocol. [Copyright &y& Elsevier]

Abstract: The synthesis of novel tetracyclic fused pyrroles from 1-(2-iodophenyl)-1H-pyrrole and various bromoalkyl-aryl alkynes via a palladium(0)-catalyzed and norbornene-mediated threefold domino reaction is reported. PdCl2 and tri-2-furylphosphine (TFP) in the presence of norbornene and Cs2CO3 in CH3CN at 90°C gave a variety of tetracyclic fused pyrroles in usually high yields. In the described reaction sequence two of the three carbon–carbon bonds are formed by functionalization of an unactivated aryl C–H bond. [Copyright &y& Elsevier]

Abstract: A facile and versatile procedure for the synthesis of 5-hetaryl-3-(2-hydroxybenzoyl)-1H-pyrroles and 4-(2-hydroxybenzoyl)-1H-pyrrole-2-carboxylic acid derivatives was established on the basis of TMSCl promoted recyclization of 3-formylchromone with various hetarylmethylamines and glycine derivatives. [Copyright &y& Elsevier]

Abstract: Topsentins and related bis-indole alkaloids may be efficiently synthesized through an addition/oxidation sequence leading to 2-(3-indolylcarbonyl)-imidazole derivatives followed by a Pd-catalyzed heteroarylation with the appropriate 3-stannylindoles. [Copyright &y& Elsevier]

Abstract: In addition to the known dihydroxystyrylguanidine alkaloid tubastrine (1), five new dimers, orthidines A–E (2–6) and the biosynthetically unrelated 1,14-sperminedihomovanillamide (orthidine F, 7) were isolated from the New Zealand ascidian Aplidium orthium. The structures of the new compounds, elucidated by interpretation of spectroscopic data, encompass benzodioxane neolignan-type scaffolds (2–5) and a 1,2,3,4-tetrasubstituted cyclobutane (6), the latter likely having arisen via [π2s+π2s] dimerization of tubastrine. The subunit head-to-tail orientation of dimer 6 was established unambiguously by interpretation of data from a 2 J,3 J-HMBC NMR experiment. The structure of 7 was also confirmed by facile synthesis. Compounds 1–4, 6, and 7 inhibited the in vitro production of superoxide by PMA-stimulated human neutrophils in a dose-dependent manner with IC50s of 10–36μM and this was associated with inhibition of superoxide production by neutrophils in vivo in a murine model of gouty inflammation. [Copyright &y& Elsevier]

Abstract: Methyl pyropheophorbide-d possessing a formyl group at the 3-position and its regioisomer having 8-CHO were prepared and their reactivities with a reductant were determined by the 1H NMR technique: 3-CHO>8-CHO. The regioselective reduction of a synthetic 3,8-diformyl-chlorin also supported the higher reactivity in 3-CHO than in 8-CHO. Regiodependent reduction of the corresponding acetyl-chlorins confirmed that carbonyl groups at the 3-position in chlorophyllous pigments were reduced more rapidly than those at the 8-position. From the reports that reactions of 3-CHO with amines were preferable to those of 7-CHO, the Cnal groups on the pyrrole A-ring of chlorophylls are more reactive than those on the B-ring. [Copyright &y& Elsevier]

Abstract: New indolizidines, quinolizidines, and octahydro-pyrido[1,2-a]azepines of lactam type were synthesized from 2-nitromethylene-pyrrolidine, -piperidine, and -hexahydroazepine, respectively, by [3+3] cyclizations with α,β-unsaturated carboxylic acid chlorides. In the case of quinolizidines, a double bond migration was observed, and explained in terms of amidity percentage. Cyanomethylene-pyrrolidine gave indolizidines of lactam type, while transformations of 1-cyanomethylene-tetrahydoisoquinoline resulted in lactams as well as ketones, when simple open-chain acid chlorides or cinnamoyl chloride were used, respectively. [Copyright &y& Elsevier]

Abstract: The solvent-free interaction of 2-phenylpyrrole with bromobenzoylacetylene (room temperature) upon their grinding with solid metal oxides (MgO, CaO, ZnO, BaO, Al2O3, TiO2, ZrO2) and salts (CaCO3, ZrSiO4) leads to either the cross-coupling product or the adduct of pyrrole addition to the riple bond of acetylene. The ethynylation is accompanied by the formation of intermediate and side products: E-2-(1-bromo-2-benzoylethenyl)-5-phenylpyrrole and 1,1-di(5-phenylpyrrol-2-yl)-2-benzoylethene. The activity of the metal oxides in the ethynylation reaction falls in the order (in the brackets, the content of 2-benzoylethynyl-5-phenylpyrrole in the reaction mixture is given): ZnO (81%), BaO (73%), Al2O3 (71%), MgO (69%), CaO (50%). The oxides, SiO2, TiO2, ZrO2, and the salts, CaCO3 and ZrSiO4, are inactive in the ethynylation reaction affording only the intermediate adduct, with ZrO2 the isolated yield of the bromoethenylpyrrole reaching 60%. ESR monitoring shows the reaction to start from one electron transfer from pyrrole to acetylene mediated by the oxide surface. The adduct is readily converted on Al2O3 to 2-(benzoylethynyl)-5-phenylpyrrole crystallized mostly as cis-rotamer (X-ray data). [Copyright &y& Elsevier]

Abstract: The first total synthesis of the antimalarial naphthylisoquinoline alkaloid 5-epi-4′-O-demethylancistrobertsonine C (1a) and its—as yet unnatural—atropo-diastereomer, 1b, is described. The key step of the synthesis is the construction of the rotationally hindered and thus stereogenic biaryl axis, which was built up by a Suzuki reaction. The use of chiral ligands in the palladium-catalyzed cross-coupling permitted to increase the low internal asymmetric induction up to a diastereomeric ratio of 74:26. The assignment of the axial configurations of the atropo-diastereomers was achieved by 2D NMR experiments and corroborated by quantum chemical CD calculations. [Copyright &y& Elsevier]

Abstract: Aryl imines formed from aldehydes and amines undergo smoothly in situ nucleophilic addition with trimethylsilyl cyanide (TMSCN) in the presence of catalytic amount of hydrated rhodium(III) iodide to afford the corresponding α-aminonitriles in excellent yield. The low catalytic loading (2mol%), mild experimental conditions, and short reaction time (mostly within 13min) represent the key features of this novel catalytic system. [Copyright &y& Elsevier]

Abstract: Ethyl 3-nitro-2-alkenoates can be generated starting from nitroalkanes and ethyl 2-oxoacetate under heterogeneous conditions that minimize work-up procedures, avoid any purification step and direct manipulation of the nitroalkene system. Reaction of ethyl 3-nitro-2-alkenoates, formed in situ from their acetoxy precursors, with indoles in the presence of basic alumina affords ethyl 2-(3-indolyl)-3-nitroalkanoates that are central intermediates for the preparation of tryptamines and carboline alkaloids. A base promoted elimination of nitrous acid from these nitroindolyl derivatives readily produces ethyl 2-(3-indolyl)-2-alkenoates with high E stereoselectivity. The latter compounds can be used as Michael acceptors in intra- and intermolecular reactions with nucleophilic reagents. [Copyright &y& Elsevier]

Abstract: An efficient copper-catalyzed N-arylation and N-heteroarylation reactions of imidazole, pyrrole, indole, pyrazole, and perimidine with aryl or heteroaryl halides using pyridine-functionalized 1,3-diketone as ligands have been investigated. The ligands bearing pyridyl and 1,3-diketone moieties, which may form chelated Cu(I) species, are inexpensive and readily available. The combination of CuI and 1,3-di(pyridin-2-yl)propane-1,3-dione is very efficient for C–N coupling reactions to afford various N-arylated products in good to excellent yields. [Copyright &y& Elsevier]

Abstract: A new approach to the core structure of protoberberine alkaloid was described. Total synthesis of (±)-gusanlung D (2) was reported. [Copyright &y& Elsevier]

Abstract: The chemo- as well as regioselective imino Diels–Alder reactions of 5-dienyl pyrimidinones with N-aryl as well as N-naphthyl imines in the presence of a different Lewis acid catalysts resulting in novel quinoline and benzoquinoline derivatives are reported. [Copyright &y& Elsevier]

Abstract: We report a synthetic route to ansa pyrrole amino acids via olefin ring-closing metathesis of diene precursors in the presence of Grubbs I catalyst. The dienes were prepared by Grignard addition to pyrrole sulfinyl imines. The success of the macrocyclic ring closure depends on the dienes structure and only in the case of the 13-membered compound 28 sufficient material could be isolated by preparative HPLC separation to investigate its structure spectroscopically. As also rationalized by our computations at the B3LYP/6-311+G(d,p)//B3LYP/6-31G(d) level of theory, 28 is configurationally stable. [Copyright &y& Elsevier]

Abstract: Starting from 4-bromo-Uhle''s ketone (2), an alkylation step using ethyl 3-methylamino-propionate followed by intramolecular aldol condensation in two steps, transformation of the ester group into a methyl group, and finally cyclopropanation of the 8,9 double bond, resulted in a six-step total synthesis of (±)-cycloclavine (1). [Copyright &y& Elsevier]

Abstract: The neutral zirconium(IV) bis(thiophosphinic amidate) complex was demonstrated to be an effective precatalyst for 5-exo-, 6-exo-, and 7-exo-dig intramolecular hydroamination of aminoalkynes, producing the cyclic imines in excellent yields (92–98%). [Copyright &y& Elsevier]

Abstract: (±)-Indolizidines 167B and 209D, their epimers and (±)-tashiromine have been successfully synthesized, starting from simple γ- or α-lactams. The strategy involves the cyclization of α-sulfinyl carbanion onto the carbonyl group of the lactam ring as the key step, leading to the indolizidines containing the phenylsulfinyl group, which are used as precursors for the preparation of the title compounds. [Copyright &y& Elsevier]

Abstract: An efficient method for the asymmetric synthesis of the trifluoromethylated propargylamines was described. Addition of lithium trifluoromethylacetylide, in situ prepared from lithium diisopropylamide and the 2-bromo-3,3,3-trifluoropropene, to various N-tert-butanesulfinyl imines provided a range of trifluoromethylated propargyl sulfinamides. Besides high yields and excellent diastereoselectivities, the additions featured that the diastereoselectivities could be reversed when polar or nonpolar solvent was used. Acidic cleavage of the tert-butanesulfinyl groups delivered highly optically pure trifluoromethylated propargylamines. [Copyright &y& Elsevier]

Abstract: For the first time a reaction intermediate has been isolated giving further insight into the mechanism of thiazol-2-imine formation. The first step of the reaction requires a basic medium, while the second step is an acid mediated E1 elimination reaction. An efficient one-pot synthesis of substituted thiazol-2-imines have been achieved by the condensation of carbonyl compounds with thioureas and 1,3-disubstituted thioureas using 1,1′-(ethane-1,2-diyl)dipyridinium bistribromide (EDPBT). Unsymmetrical 1,3-disubstituted thioureas give regioselective products with symmetrical ketones, which are mainly governed by the pK as of NH protons of thiourea, whereas symmetrical 1,3-disubstituted thioureas give regioselective products with symmetrical carbonyl compounds owing to the regioselective bromination of ketones. The methodology is extended to access novel neurodegenerative drug candidate pifithrin-α analogues in good yields in shorter reaction time. This method is simple, versatile and is applicable for different 1,3-disubstituted thioureas as well as a range of carbonyl compounds. [Copyright &y& Elsevier]

Abstract: Six new Daphniphyllum alkaloids, calyciphyllines H–M (1–6), were isolated from the leaves and stems of Daphniphyllum calycinum (Daphniphyllaceae). The structures and relative stereochemistry of 1–6 were elucidated on the basis of spectroscopic data, and the absolute stereochemistry of 3 was assigned by PGME method. [Copyright &y& Elsevier]

Abstract: The intermolecular reductive coupling of aromatic imines with acylimidazoles was effected by electroreduction in the presence of chlorotrimethylsilane and gave α-amino-α-aryl ketones. This method was also effective for the synthesis of α-amino-α-aryl esters using methoxycarbonylimidazole as an electrophile. [Copyright &y& Elsevier]

Abstract: The syntheses of indolizidine alkaloids, i.e., (±)-coniceine, (±)-indolizidine 167B, (±)-5-butylindolizidine and (±)-monomorine I via Pummerer cyclization are described. The key step is the transformation of lactam sulfoxide to bicyclic lactam via the Pummerer cyclization. [Copyright &y& Elsevier]

Abstract: A chiral ionic liquid-catalyzed, efficient and unprecedented version of the Biginelli reaction using new variants of its active methylene component, viz. 2-phenyl-1,3-oxazol-5-one/2-methyl-2-phenyl-1,3-oxathiolan-5-one, with aromatic aldehydes and urea/thiourea enantio- and diastereoselectively, yields 5-amino-/mercaptoperhydropyrimidines. This three-component domino cyclocondensation reaction is effected via ring transformation of an isolable intermediate in a one-pot procedure. [Copyright &y& Elsevier]

Abstract: The addition of boronic acids to five- and six-membered ring N-acyliminium ions has been employed to prepare 5- and 6-substituted 4-hydroxypyrrolidin-2-ones and 5-hydroxypiperidin-2-ones, respectively, in a diastereoselective fashion. [Copyright &y& Elsevier]

Abstract: A total of 16 alkaloids, exemplified by mersinine A and its congeners, and constituting a new subclass of the monoterpenoid indoles, were isolated exclusively and for the first time from Kopsia singapurensis. The structures of these alkaloids were established by spectroscopic methods and in some instances confirmed by X-ray diffraction analysis. A possible biogenetic route from an aspidofractinine precursor is proposed. Compounds 1, 2, 3, 9, and 10 were found to reverse multidrug-resistance in drug-resistant KB cells. [Copyright &y& Elsevier]

Abstract: Addition of organometallic reagents to optically active methyl 1-(2-methoxycarbonyl-6-trifluoromethylphenyl)pyrrole-2-carboxylate provided the corresponding tetrasubstituted diols and/or pyrrolo[1,2-a]benzoxazepines as pure enantiomers or racemates depending on the organometallic reagents used. Rotational energy barriers around the interconnecting C–N bonds were estimated by molecular modeling calculations and NMR measurements with the aim of clarifying the stereochemical stability order of the new atropisomeric compounds. NMR methods for the determination of the enantiomeric purity of the new compounds are proposed. [Copyright &y& Elsevier]