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The synthesis of differently substituted 2,3,4-triarylcyclopent-2-en-1-ones from 2-cyclopentenone via sequential functionalization of a novel 2,4-dibromo-3-(4-methoxyphenyl) cyclopent-2-en-1-one intermediate has been developed. The process provides access to selective arylation at C-4 and C-2 with a broader substrates scope, which includes heteroaryl and alkyl substitution at C-2.

In the present work the phase transition and its dependence on target excitation has been studied in two dimensional ( η − φ ) self affine space using the experimental data of pions obtained from π − -AgBr interactions at 350 GeV/c. For studying target excitation dependence the data for produced pions are divided into three sets depending on the number of grey particles ( ng ). The different sets corresponds to the different degrees of target excitation. The Levy indices µ measured from the analysis fulfills the requirement of the levy stable region 0 ≤ µ ≤ 2 . The Levy index µ

Trifluoromethyl containing heterocycles are an integral part of many biologically active compounds in the agro and pharmaceutical chemistry. Herein, we report an efficient and concise three-step synthesis of 5-halo-6-trifluoromethylpyridine-3-carbonitriles from a trifluoroacetyl vinylogous enamine starting material. Hydrolysis furnishes the carboxylic acids.

Diversely functionalized nitrogen-containing heteroaromatic building blocks, fine chemicals and active pharmaceutical or agrochemical ingredients are conveniently prepared via CN bond formation as the key step. Since beginning of the last decade, there has been a flurry of intense research in forging CN bonds using iron catalysts due to their low cost, high natural abundance and non-toxic nature. The present review offers an overview of CN bond forming reactions involving aryl, allyl, propargyl and unactivated alkyl electrophilic substrates with nitrogen nucleophiles via the regular cross coupling reactions catalyzed by iron. In the miscellaneous section, a set of novel transformations facilitated by iron are included as well.

A simple, and efficient synthesis of 2,2-difluoro-3H-benzothiophen-3-ol using readily available sodium chlorodifluoroacetate (SCDA) is reported. We also explore new chemistry of these difluoro compounds. The salient feature of this approach includes operational simplicity and offers potential access to synthetically challenging building blocks for further elaboration. Functional group transformations of this new heterocycle are also presented.

Derivatives of anthranilic acid exhibit a range of useful biological activities. Herein we describe an efficient synthetic route to 1,3-benzothiadiazin-4(3H)-one 2-oxides via copper-catalyzed N-arylation of sulfonimidamides followed by cyclization. Such 1,3-benzothiadiazin-4(3H)-one 2-oxides can be viewed as novel anthranilic acid derivatives.

A convenient synthesis of 3-hydroxyquinolines has been described via unprecedented Dakin oxidation of quinoline-3-carboxaldehydes. Subsequently, application of the methodology to a high yielding synthesis of quinoline alkaloid Jineol (1) is reported.

Benzoxazole alkaloids exhibit a diverse array of structures and interesting biological activities. In spite of the extensive research done on the synthesis and biology, till date there is no concise update on this class of alkaloids. This chapter summarizes the literature on benzoxazole alkaloids till March 2017, which covers their isolation, characterization, possible biosynthetic origins, biological activities, and major synthetic approaches. These alkaloids have been broadly classified in the context of their sources, namely (i) fungal origin, (ii) marine origin, and (iii) plant origin.

Concise and efficient syntheses of nataxazole and AJI9561 have been accomplished. We also demonstrate a convenient route to obtain the related natural product UK-1. The key step involves C–H activation of a benzoxazole in the presence of ortho -iodoanilides using a copper(I) iodide/Xantphos/palladium(II) acetate system.

Using CuI/xantphos/Pd(OAc)2 catalytic system, the intermolecular C–C cross coupling between benzoxazoles and ortho-haloanilides has been developed in moderate to good yields. The procedure tolerates a series of functional groups on benzoxazole, such as ester, chloro, methyl, and methoxy groups. This divergent approach provides access to various N-(2-Benzoxazol-2-ylphenyl)amides.

A bio-catalyzed N-formylation reaction of different amines has been developed using ethyl formate as a formylating agent. This protocol provides a facile and convenient strategy featuring mild reaction conditions, high efficacy, a broad substrate scope and recyclability of lipase. This method also works on a large scale in high yield.

In the present work target excitation dependence of the self-similar cascading rate has been studied in detail in the framework of Levy stable law using the experimental data of pions obtained from π −-AgBr interactions at 350 GeV/c. TheLevy indices µ measured from the analysis fulfill the requirement of the Levy stable region 0 ⩽ µ ⩽ 2. The study gives an evidence of self-similar cascading mechanism responsible for multiparticle production. The different values of µ indicate different rates of cascading for different degrees of target excitation. Moreover, the values of universal scaling exponent (ν) obtained from Ginzburg-Landau theory indicate that no clear evidence of second-order phase transition has been found in the interaction.

A convenient and high yielding total synthesis of phebalosin (1) has been achieved in four linear steps from commercially available umbelliferone. The first total synthesis of murraxocin (4), a natural product isolated from Murraya exotica has been described via phebalosin. Total syntheses of murrangatin (2) and murralongin (5) have also been demonstrated using the same strategy. The key step involves a Corey–Chaykovsky reaction to construct the isopreneepoxide unit.

A general synthetic route to six-membered cyclic N-aryl- and N-alkyl-substituted sulfonimidamides via an intramolecular ring closure of suitably functionalised acyclic sulfonimidamides is described. The structure of this new ring system was confirmed by various analytical methods and in one example by X-ray structural analysis.

A concise first access to nataxazole (IVa) and AJI9561 (IVb) is elaborated which is also applicable to a new preparation of the natural product UK-1 (IVc).

Event-to-event fluctuation pattern of pions produced by proton and pion beams is studied in terms of the newly defined erraticity measures χ(p, q), $\chi_q^{\prime}$ and $\mu_q^{\prime}$ proposed by Cao and Hwa. The analysis reveals the erratic behaviour of the produced pions signifying the chaotic multiparticle production in high-energy hadron–nucleus interactions (π − –AgBr interactions at 350 GeV/c and p–AgBr interactions at 400 GeV/c). However, the chaoticity does not depend on whether the projectile is proton or pion. The results are compared with the results of the VENUS-generated data for the above interactions which suggests that VENUS event generator is unable to reproduce the event-to-event fluctuations of spatial patterns of final states. A comparative study of p–AgBr interactions and p–p collisions at 400 GeV/c from NA27, with the help of a quantitative parameter for the assessment of pion fluctuation, indicates conclusively that particle production process is more chaotic for hadron–nucleus interactions than for hadron–hadron interactions.

Erraticity analysis using the gap moment method is performed using the experimental data of π−–AgBr interactions at 200 and 350 GeV both for pions and compound hadrons (pions + protons). The entropy like quantity Sq has been calculated at two different energies. The variation of Sq with q and their dependence on multiplicity of charged particles are investigated also. The study reveals the positive indication of the presence of erratic nature of event-by-event fluctuations of gap distributions of produced pions and compound hadrons in emission angle (cos θ) space in relativistic hadron–nucleus interaction.

Nakamura and Kudo proposed a scaling form for charged particle pseudorapidity distributions on the basis of scaling in the mean hypothesis. This scaling form was tested primarily for hadron–hadron interaction data. But no attempt was made to verify this for hadron–nucleus interaction which offers unique opportunity to learn about the space–time structure of a strongly interacting process. In view of this we report an analysis of p–AgBr interaction data at 400 GeV/c and 200 GeV/c, π-–AgBr interaction data at 200 GeV/c and 350 GeV/c to test its (Nakamura–Kudo scaling) validity in hadron–nucleus interaction. In all cases the data show a remarkable agreement with the scaling behavior of Nakamura and Kudo.

The paper reports a study revealing self-affine fluctuations in pion, proton, and compound multiplicity (of pions combined with protons) spectra obtained from the interactions of 350 GeV pions with AgBr nuclei. The study is performed in the transformed two-dimensional phase space of the emission and azimuthal angles using the factorial moment methodology and the concept of the Hurst exponent. Evidence of a nonthermal phase transition is obtained for self-affine fluctuations of pions along with an indication for such a regime to be seen in similar fluctuations of proton and compound multiplicity distributions. The study bridges the anisotropic nature of the multiparticle production process and an evidence of the nonthermal phase transition with similar earlier findings from hadron–hadron and nucleus–nucleus interactions and shows the same effects to be peculiar features of the multiplicity distributions of the different species of particles produced. All this brings important information about the underlying dynamics of the hadroproduction process.PACS Nos.: 25.80.Hp, 24.60.Ky, 13.85.–t

This paper reports a study on multidimensional fractal behavior of pions emitted in 16 O - AgBr interactions at 2.1 and 60 AGeV by dividing the full bin range into different sub-bin ranges. Analysis is performed in (Xη - Xϕ) space following two-dimensional factorial moment methodology using the concept of Hurst exponent, which takes into account the anisotropy of phase space. Different scaling behavior is observed in different bins at two different energies. The data show a positive evidence of change of fluctuation pattern from self-similarity to self-affinity with increase of energy. Multifractal dimensions have been calculated in each case and it is observed that pions at both energies exhibit multifractal behavior.

A self-affine analysis of charged-particle multiplicity distribution (protons + pions) in π−-AgBr interaction at 350 GeV/c is performed according to the two-dimensional factorial moment methodology using the concept of Hurst exponent in Xcosθ-Xϕ phase space. Comparing with the results obtained from self-similar analysis, the self-affine analysis shows a better power-law behaviour. Corresponding results are compared with shower multiplicity distribution (pions). Multifractal behaviour is observed for both types of distributions.

Optimized conditions to favor the intermolecular metal-catalyzed transformation over the intramolecular ring closure of 2-iodoanilides are presented.

Different fractal methods (Factorial moment, Takagi moment) have been used for the analysis of fractal behavior of multiparticle production in π-- AgBr interaction at 350 GeV/c of compound multiplicity distribution in emission angle (cos θ) space and azimuthal angle (ϕ) space. The generalized fractal dimensions Dq are determined according to two methods. Results indicate multifractal behavior in compound multiplicity distribution. From the knowledge of Dq, the multifractal specific heat is calculated. Results are compared with the corresponding results of shower multiplicity.

We report new ruthenium-catalyzed cis – trans isomerization of various functionalized epoxides. Enantiospecific isomerization of chiral epoxides is achieved without loss of enantiopurity, and epimerization occurs only at the epoxide carbon of the activating group.

Title compounds (V) are prepared via an intramolecular ring closure of suitably functionalized acyclic sulfonimidates (IV).

A high yield stereoselective synthesis of 4a-angularly methyl substituted cis-hexahydrofluorenes 5a-h and tetrahydrofluorenes 7a,b has been developed by palladium-catalyzed intramolecular Heck-type cyclization of the respective exo-olefins 4a-h and 4a,b through exclusive 5-exo-trig mode.

The precise mode of action of sulfoxaflor, a new nicotinic acetylcholine receptor-modulating insecticide, is unclear. A detailed understanding of the mode of action, especially in relation to the neonicotinoids, is essential for recommending effective pest management practices.Radiolabel binding experiments using a tritiated analogue of sulfoxaflor ([(3) H]-methyl-SFX) performed on membranes from Myzus persicae demonstrate that sulfoxaflor interacts specifically with the high-affinity imidacloprid binding site present in a subpopulation of the total nAChR pool. In competition studies, imidacloprid-like neonicotinoids displace [(3) H]-methyl-SFX at pM concentrations. The effects of sulfoxaflor on the exposed aphid nervous system in situ are analogous to those of imidacloprid and nitenpyram, and finally the high-affinity sulfoxaflor binding site is absent in a Myzus persicae strain (clone FRC) possessing a single amino acid point mutation (R81T) in the β-nAChR, a region critical for neonicotinoid interaction.The nicotinic acetylcholine receptor pharmacological profile of sulfoxaflor in aphids is consistent with that of imidacloprid. Additionally, the insecticidal activity of sulfoxaflor and the current commercialised neonicotinoids is affected by the point mutation in FRC Myzus persicae. Therefore, it is suggested that sulfoxalfor be considered a neonicotinoid, and that this be taken into account when recommending insecticide rotation partnering for effective resistance management programmes.

The stereocontrolled synthesis of trans-octahydroanthracenes (3), (11a- c), and (14a-c) and trans-octahydro-5aH-cyclohepta[b] naphthalene (27) through implementation of an efficient and highly regioselective 6-endo -trig-aryl radical cyclization of the respective 2-(o-bromoaryl)-1-me- thylenecyclohexanes (2), (10a-c), and (13a-c) and 2-(o-bromobenzyl)-1- methylenecycloheptane (41) with tri-n-butyltin hydride is described. The radical cyclization of 2-(o-bromobenzyl)-1-methylenecyclopentane (43), in contrast, produced a mixture of the cis- and trans-hexahydro- 1H-benz[f]indenes (38) and (37)

The previously assigned (ref.1) ortho-cycloalkylated product from the reaction of 1 and 2 respectively, with ortho-phosphosphoric acid and polyphosphoric acid, has been corrected to (±)-4-methoxy-9a-carbamorphinan-16-one (6) and the respective ether 7 by a single crystal X-ray structure determination of 6.

The bridged-ethers, (±)-2-methoxy-9a-carbamorphinan (1b) and (±)-2-methoxy-9a-carba-14α-morphinan(2b) have been synthesized. The acid-catalyzed cyclizations of 1-m-methoxy benzyloctalone 3b and 1-m-methoxybenzyloctalins 4b proceed with high regio-and stereoselectivities leading mostly to the bridged-ketone 14 and ether 1b respectively, along with o-methoxy-tetracyclic ketone 15 and the ether 17, in addition to other minor products.

Loline alkaloids are saturated pyrrolizidines with an oxygen bridge between carbon atoms C-2 and C-7 and an amino group on C-1. They are bioprotective alkaloids produced by Epichloe and Neotyphodium species, mutualistic fungal endophytes that are symbiotic with cool-season grasses. The sequence of bond formation in loline alkaloid biosynthesis was determined by synthesizing deuterated forms of potential intermediates and feeding them to cultures of the endophyte Neotyphodium uncinatum. These cultures incorporated deuterium from labeled N-(3-amino-3-carboxypropyl)proline and exo-1-aminopyrrolizidine into N-formylloline. The first result suggests that N-(3-amino-3-carboxypropyl)proline is the first committed intermediate in loline biosynthesis, and the second result demonstrates that the pyrrolizidine rings form before the ether bridge. The incorporation of these two compounds into lolines and the lack of incorporation of several related compounds clarify the order of bond formation in loline alkaloid biosynthesis.

Treatment of a series of 2',2'-disubstituted (o-ethynyl)styrenes with TpRu(PPh(3))(CH(3)CN)(2)PF(6) (10 mol %) in benzene (80 degrees C, 12-18 h) efficiently gave 2-alkenyl-1H-indene derivatives. This catalytic reaction represents an atypical enyne cycloisomerization with skeletal rearrangement of starting enyne, where the C=C bond is completely cleaved and inserted by the terminal alkynyl carbon. The reaction mechanism was elucidated by a series of deuterium and (13)C labeling experiments, as well as by changing the substituents at the phenyl moieties. The mechanism is proposed to involve the following key steps: 5-endo-dig cyclization of ruthenium-vinylidene intermediate, a nonclassical ion formation, and the "methylenecyclopropane-trimethylenemethane" rearrangement.

The halo and aryl substituents of the 1,2-disubstituted styryl group of aromatic enynes undergo a 1,2-shift in the aromatization reaction catalyzed by TpRuPPh3(CH3CN)2PF6 (10 mol %) in toluene (110 degrees C, 6-8 h). The aryl group shifts to the neighboring olefin carbon, and the iodo (or bromo) substituent migrates to the terminal alkyne carbon. The mechanisms of these two migrations have been elucidated by isotope labeling experiments. It indicates that the 1,2-aryl shift arises from 5-endo-dig electrocyclization of a ruthenium-vinylidene species, whereas the 1,2-iodo shift follows a 6-endo-dig pathway.

We report new ruthenium-catalyzed cis – trans isomerization of various functionalized epoxides. Enantiospecific isomerization of chiral epoxides is achieved without loss of enantiopurity, and epimerization occurs only at the epoxide carbon of the activating group.

In this paper, a detailed study of the chaotic behavior of compound hadrons (pions plus protons) in ???AgBr interactions at 350?GeV c?1 has been performed with the help of the parameter 'entropy index' ?q, which is a measure of the chaotic behavior in multipion production processes. This index describes the event-to-event fluctuation of factorial moments that measures the spatial fluctuation of multiplicity distribution. The analysis reveals a large value for the entropy index signifying the chaotic behavior of the produced compound hadrons in high-energy hadron?nucleus interactions. It was been observed that the multipion production process becomes less chaotic with increasing average multiplicity of the final states. The study has been further extended to pions, and the corresponding results are compared.

In this paper a detailed study on the erratic behaviour of multiparticle production in π - -AgBr interactions at 350 GeV has been performed with the help of the parameter 'entropy index' μ q , which is a measure of chaotic behaviour in multipion production processes. This index describes the event-to-event fluctuation of factorial moments which measures the spatial fluctuation of multiplicity distribution. The analysis reveals a large value for the entropy index, signifying the chaotic behaviour of the produced pions in high-energy hadron-nucleus interactions. It has been observed that the multipion production process becomes less chaotic with an increasing average multiplicity of the final states. The study has further been extended to know the target excitation dependence of chaoticity of pions; a positive dependence is indicated by the data.

Loline alkaloids are saturated pyrrolizidines with a substituted 1-amino group and an oxygen bridge between C2 and C7, and are insecticidal metabolites of plant-symbiotic fungi (endophytes). Cultures of the endophyte, Neotyphodium uncinatum, incorporated labeled L-proline and L-homoserine into the 1-aminopyrrolizidine, N-formylloline. The A-ring carbons C1-C3 and the N1 were derived from L-homoserine; the B-ring carbons C5-C8 and the ring nitrogen were derived from L-proline. Incorporation of both deuterium atoms from L-[4,4-(2H2)]homoserine and feeding tests with labeled L-methionine indicated that L-homoserine incorporation was not achieved via aspartyl semialdehyde or S-adenosylmethionine, but probably involved a highly novel N--C bond-forming gamma-substitution reaction.

The acid-catalysed reaction of the 1-diazoacetyltetrahydrophenanthrene 1a and the three new related diazoketones 1b–d gave, in addition to the respective bridged ketones 2a–d and the pentaleno annelated ketones 3a–d, the acephenanthrones 4a–d, which were also prepared in excellent yield by the rhodium(II) acetate-induced reaction of the diazoketones.

A highly efficient 7-endo-trig-aryl radical cyclisation of the alkene 6 and the vinylcyclohexanols 11a–d with tri-n-butyltin hydride leading to the respective octahydro-2H-dibenzo[a,d]cycloheptene derivatives 7 and 8 and 12a–d is reported.

The sterocontrolled synthesis of trans-octahydroanthracenes 3, 11 and 14 through implementation of an efficient and highly regioselective 6-endo-trig-aryl radical cyclisation of the respective 2-(o-bromobenzyl)-1-methylenecyclohexanes 2, 10 and 13, with tri-n-butyltin hydride is reported, along with a single crystal X-ray structure determination of 11.