Silver-Catalyzed Cascade Radical Cyclization: A Direct Approach to 3,4-Disubstituted Dihydroquinolin-2(1H)-ones through Activation of the P-H Bond and Functionalization of the C(sp(2))-H Bond.

A silver-catalyzed cascade cyclization of cinnamamides with diphenylphosphine oxide was developed, in which activation of the P-H bond and functionalization of the C(sp(2))-H bond occurred. A direct method for the synthesis of 3,4-disubstituted dihydroquinolin-2(1H)-ones was developed.

Organocatalytic one-pot synthesis of highly substituted pyridazines from Morita-Baylis-Hillman carbonates and diazo compounds.

A biologically inspired organocatalytic one-pot synthesis of highly functionalized pyridazines, which are ubiquitous structural units in a number of biologically active compounds, has been developed by starting from readily available diazo compounds and Morita-Baylis-Hillman (MBH) carbonates. Under mild reaction conditions, this synthetic route tolerated significant substrate variation to deliver a broad range of substituted products, including CF3 -substituted pyridazines derivatives. Moreover, the introduction of trifluoromethyl groups into the ring of pyridazine could be completed conveniently from 2,2,2-trifluorodiazoethane.

Azocinoindole synthesis by a gold(I)-catalyzed ring expansion of 2-propargyl-ß-tetrahydrocarboline.

A new methodology taking advantage of gold(I)-catalyzed ring expansion has been developed to assemble tricyclic 1H-azocino[5,4-b]indoles from 2-propargyl-ß-tetrahydrocarbolines. The azocinoindoles were obtained in moderate to excellent yields; the structure of which was established by X-ray crystallographic analysis. A mechanism involving regioselective intramolecular hydroarylation, [1,2]-alkenyl migration and carbon-carbon bond-fragmentation was proposed.

Synthesis of functionalized isoquinolin-1(2H)-ones by copper-catalyzed α-arylation of ketones with 2-halobenzamides.

Copper is key: A concise route to isoquinolin-1(2H)-ones from simple and readily available starting materials is provided by an efficient copper-catalyzed annulation of ketones with 2-halobenzamides. The method is applicable to a wide range of ketones containing different functional groups furnishing the products in moderate to excellent yields.

Enantioselective construction of spirooxindole derivatives through [3+2] annulation catalyzed by a bisthiourea as a multiple-hydrogen-bond donor.

Anything between ureas? Spiro[isoxazolidine-3,3'-oxindole]s have been constructed by employing methyleneindolinones and nitrones as the starting materials through [3+2] annulation catalyzed by a bisthiourea. Products with three contiguous stereocenters, including one spiroquaternary stereocenter, are obtained in good yields with excellent enantio- and diastereoselectivity. The bisthiourea catalyst acts as a multiple-hydrogen-bond donor to simultaneously activate both substrates.

Cu-catalyzed direct C-H bond functionalization: a regioselective protocol to 5-aryl thiazolo[3,2-b]-1,2,4-triazoles.

An efficient, regioselective C-5 arylation of thiazolo[3,2-b]-1,2,4-triazoles catalyzed by a simple copper catalyst was developed. This arylation proceeded smoothly and tolerated a variety of functional groups (44 examples). A wide range of functionalized thiazolo[3,2-b]-1,2,4-triazole derivatives were obtained in high yields (up to 99% yield). Possible catalytic cycles of the arylation were also discussed.

Intelligent multicast routing method based on multi-agent deep reinforcement learning in SDWN.

Multicast communication technology is widely applied in wireless environments with a high device density. Traditional wireless network architectures have difficulty flexibly obtaining and maintaining global network state information and cannot quickly respond to network state changes, thus affecting the throughput, delay, and other QoS requirements of existing multicasting solutions. Therefore, this paper proposes a new multicast routing method based on multiagent deep reinforcement learning (MADRL-MR) in a software-defined wireless networking (SDWN) environment. First, SDWN technology is adopted to flexibly configure the network and obtain network state information in the form of traffic matrices representing global network links information, such as link bandwidth, delay, and packet loss rate. Second, the multicast routing problem is divided into multiple subproblems, which are solved through multiagent cooperation. To enable each agent to accurately understand the current network state and the status of multicast tree construction, the state space of each agent is designed based on the traffic and multicast tree status matrices, and the set of AP nodes in the network is used as the action space. A novel single-hop action strategy is designed, along with a reward function based on the four states that may occur during tree construction: progress, invalid, loop, and termination. Finally, a decentralized training approach is combined with transfer learning to enable each agent to quickly adapt to the dynamic changes of network link information and accelerate convergence. Simulation experiments show that MADRL-MR outperforms existing algorithms in terms of throughput, delay, packet loss rate, etc., and can establish more intelligent multicast routes. Code and model are available at https://github.com/GuetYe/MADRL-MR_code.

Effects of forage type on the rumen microbiota, growth performance, carcass traits, and meat quality in fattening goats.

Forages fed to goats influence ruminal microbiota, and further contribute to affect growth performance, meat quality and its nutritional composition. Our objective for current study was to investigate the effects of different forages on growth performance, carcass traits, meat nutritional composition, rumen microflora, and the relationships between key bacteria and amino acids and fatty acids in the longissimus dorsi and semimembranosus muscles of goats. Boer crossbred goats were separately fed commercial concentrate diet supplemented with Hemarthria altissima (HA), Pennisetum sinese (PS), or forage maize (FG), and then slaughtered 90 days after the beginning of the experiment. Growth performances did not vary but carcass traits of dressing percentage, semi-eviscerated slaughter percentage, and eviscerated slaughter percentage displayed significant difference with the treatment studied. Meats from goats fed forage maize, especially semimembranosus muscles are rich in essential amino acids, as well as an increase in the amount of beneficial fatty acids. Our 16S rRNA gene sequencing results showed that the Firmicutes, Bacteroidetes, and Proteobacteria were the most dominant phyla in all groups but different in relative abundance. Further, the taxonomic analysis and linear discriminant analysis effect size (LEfSe) identified the specific taxa that were differentially represented among three forage treatments. The spearman's correlation analysis showed that rumen microbiota was significantly associated with the goat meat nutritional composition, and more significant positive correlations were identified in semimembranosus muscles when compared with longissimus dorsi muscles. More specifically, the lipid metabolism-related bacteria Rikenellaceae_RC9_gut_group showed positively correlated with meat amino acid profile, while genera Oscillospiraceae_UCG-005 were positively correlated with fatty acid composition. These bacteria genera might have the potential to improve nutritional value and meat quality. Collectively, our results showed that different forages alter the carcass traits, meat nutritional composition, and rumen microflora in fattening goats, and forage maize induced an improvement in its nutritional value.

Synthesis and enhanced DNA cleavage activities of bis-tacnorthoamide derivatives.

A new metal-free DNA cleaving reagent, bis-tacnorthoamide derivative 1 with two tacnorthoamide (tacnoa) units linked by a spacer containing anthraquinone, has been synthesized from triazatricyclo[5.2.1.0(4,10)]decane and characterized by NMR and mass spectrometry. For comparison, the corresponding compounds mono-tacnorthoamide derivative 2 with one tacnorthoamide unit and 6 with two tacnorthoamide units linked by an alkyl (1,6-hexamethylene) spacer without anthraquinone have also been synthesized. The DNA-binding property investigated via fluorescence and CD spectroscopy suggests that compounds 1 and 2 have an intercalating DNA binding mode, and the apparent binding constants of 1, 2 and 6 are 1.3 × 10(7) M(-1), 0.8 × 10(7) M(-1) and 8 × 10(5) M(-1), respectively. Agarose gel electrophoresis was used to assess plasmid pUC19 DNA cleavage activity promoted by 1, 2, 6 and parent tacnoa under physiological conditions, which gives rate constants k(obs) of 0.2126 ± 0.0055 h(-1), 0.0620 ± 0.0024 h(-1), 0.040 ± 0.0007 h(-1) and 0.0043 ± 0.0002 h(-1), respectively. The 50-fold and 15-fold rate acceleration over parent tacnoa is because of the anthraquinone moiety of compound 1 or 2 intercalating into DNA base pairs via a stacking interaction. Moreover, DNA cleavage reactions promoted by compound 1 give 5.3-fold rate acceleration over compound 6, which further demonstrates that the introduction of anthraquinone results in a large enhancement of DNA cleavage activity. In particular, DNA cleavage activity promoted by 1 bearing two tacnoa units is 3.3 times more effective than 2 bearing one tacnoa unit and the DNA cleavage by compound 1 was achieved effectively at a relatively low concentration (0.03 mM). This dramatic rate acceleration suggests the cooperative catalysis of the two positively charged tacnoa units in compound 1. The radical scavenger inhibition study and ESI-MS analysis of bis(2,4-dinitrophenyl) phosphate (BDNPP) and adenylyl(3'-5')phosphoadenine (APA) cleavage in the presence of compound 1 suggest the cleavage mechanism would be via a hydrolysis pathway by cleaving the phosphodiester bond of DNA.

[An epidemiological survey of febrile convulsions among pupils in the Wenzhou region].

OBJECTIVE: To study the prevalence and clinical features of febrile convulsion (FC) among pupils in the Wenzhou region, Zhejiang Province, China. METHODS: Using a random stratified cluster sampling method, 6406 children under 12 years from two primary schools of urban areas and two primary schools of rural areas were surveyed. RESULTS: The prevalence of FC was 3.67% (235/6406). Most children (75.7%) experienced their first onset of FC at 6 months to 3 years of age (median: 16 months). The seizures were generalized (95.3%, 224/235), with a duration of less than 10 minutes (86.4%, 203/235). FC was developed into epilepsy in 13 children (5.5%) who all suffered from complex FC. Relapses were noted in 88 cases (37.4%), among whom 38 patients had only 1 recurrence and 50 patients had 2 or more relapses. EEG was performed in 200 cases, among whom 12(6.0%) showed abnormalities. CONCLUSIONS: The prevalence of FC is 3.67% among pupils in the Wenzhou region. The seizures are generalized, with a short duration. A part of complex FC can be developed into subsequent epilepsy.

Efficiency and mechanism of a vermicompost additive in enhancing composting of swine manure.

Vermicompost was used as an additive in swine manure composting to investigate the expression of bacterial functional genes on nutrients biotransformation. Three treatments with vermicompost compositions of 10%, 20%, and 30% in swine manure were set up. Raw manure was used as the control. The thermophilic period increased to 12 days, the NH4+ -N/NO3- -N ratio decreased to 0.85, and the germination index (GI) increased to 166% after vermicompost addition. Furthermore, higher relative abundances of Firmicutes were observed in the substrate during the initial stages of experiment. The abundance of the dominant phylum Proteobacteria and its related pathogenic genera Acinetobacter and Stenotrophomonas decreased in the thermophilic stage while the potentially beneficial genera Actinomadura and Chryseolinea increased. The expression of primary functional genes associated with the metabolism of carbohydrates, amino acids, xenobiotics, and fatty acids was enhanced during the thermophilic phase. Besides, most dominant genera showed strengthened correlations with NO3--N and GI, which were the strongest environmental factors for bacterial communities. Network analysis revealed a new metabolic pathway associated with dominant genera Pseudomonas, Acinetobacter, Stenotrophomonas, and Oceanobacter, whose abundance increased with vermicompost addition. Collectively, the results of this study indicate that vermicompost can promote composting efficiency by increasing the potentially beneficial bacteria, decreasing pathogenic bacteria, and enhancing the metabolic capacity of bacterial communities.

Intermolecular photocyclizations of N-(omega-hydroxyalkyl)tetrachlorophthalimide with alkenes leading to medium- and large-ring heterocycles--reaction modes and regio- and stereoselectivity of the 1,n-biradicals.

A new photocyclization strategy by using intermolecular tandem reactions between N-(omega-hydroxyalkyl)-4,5,6,7-tetrachlorophthalimides (1, 2, and 3) and a series of acyclic and cyclic alkenes is reported. Electron transfer of the triplet-excited phthalimide with the alkene and regioselective trapping of the alkene cation radical by the hydroxyl group at the phthalimide side chain gives a triplet 1,n-biradical, which after intersystem crossing (ISC) leads to regio- and diastereoselective synthesis of polycyclic heterocycles with an N,O-containing medium to large ring. Regio- and diastereoselectivity in the cyclizations are clarified by unambiguous steric structure assignments of the products by X-ray diffraction or extensive 2D NMR measurements. The diastereoselectivity is decided by the stereochemical course of the ISC process of the triplet 1,n-biradicals. These intermolecular photoreactions also furnish a new strategy to generate triplet 1,n-biradicals. Therefore, in photoreactions of 1 and 2 with phenylcyclohexene, the unprecedented stereoselective formation of products by intramolecular hydrogen-atom transfer in the 1,n-biradical intermediate was found (9 and 23). These facts provide direct verification to the reaction pathways of the 1,n-biradicals and give a new insight into the factors deciding reaction-pathway partitioning and stereoselectivity.

Synthesis of 1,2-annulated and 1,2-unsubstituted pyrrolo[2,1,5-de]quinolizin-5-ones (cycl[3.3.2]azin-5-ones) via [3+2] cycloadditions of 1-oxoquinolizinium ylides with cyclic alkenes.

1,2-Annulated pyrrolo[2,1,5-de]quinolizin-5-ones (cycl[3.3.2]azin-5-ones) 6a-6k, 8a-8b and 9 have been synthesized by one pot tandem reactions of 2-acetyl-N-phenacylpyridinium bromides (1a-1d) with electron-deficient cyclic alkenes (N-alkyl(aryl)maleimides, benzoquinones and naphthoquinone) in the presence of sodium carbonate as a base and tetrakispyridinecobalt(II) dichromate (TPCD) as an oxidant. These products are formed by 1.3-dipolar cycloaddition of the 1-oxoquinolizinium ylides generated in situ from 1a-1d with the alkene followed by dehydrogenation of the primary cycloadduct under the action of TPCD. Similar reactions of the ylides generated in situ from 1a-1f with maleic anhydride gave the 1,2-unsubstituted pyrrolo[2,1,5-de]quinolizin-5-ones 7a-7f via oxidative bisdecarboxylation and dehydrogenation of the primary cycloadducts under the action of TPCD.

Regioselective synthesis of 3-acylindolizines and benzo- analogues via 1,3-dipolar cycloadditions of N-ylides with maleic anhydride.

3-Acylindolizines (5a-5f) and their benzo- analogues 1-acylpyrrolo[1,2-a]quinolines (6a-6f) and 1-acylpyrrolo[2,1-a]isoquinolines (7a-7i) are regioselectively synthesized by a convenient one pot reaction of the corresponding pyridinium (quinolinium, isoquinolinium) ylide with maleic anhydride (MA) in the presence of the mild oxidant tetrakispyridinecobalt(ii) dichromate (TPCD). These reactions proceed via a tandem reaction sequence of 1,3-dipolar cycloaddition of azomethine ylide with MA, anhydride hydrolysis and oxidative bisdecarboxylation of the primary cycloadducts followed by dehydrogenative aromatization of the dihydroindolizines. TPCD serves as both decarboxylation and dehydrogenation reagent in the reactions. These results show that TPCD is a promising new reagent for bisdecarboxylation of aliphatic carboxylates.

2-[3-((Z)-2-{4-[Bis(2-chloro-eth-yl)amino]-phen-yl}ethen-yl)-5,5-dimethyl-cyclo-hex-2-en-1-yl-idene]propane-dinitrile.

The highly conjugated title compound, C(23)H(25)Cl(2)N(3), is nearly planar (the mean deviation from the plane being 0.049 Å), except for the -C(CH(3))(2) group on the cyclo-hexene ring and the two CH(2)Cl groups. The cyclo-hexene ring has an envelope configuration. In the crystal, the packing is stabilized by C-H⋯Cl inter-actions and C-H⋯π inter-actions involving the benzene ring.

2-(2-Chloro-3-quinol-yl)-3-phenyl-thia-zolidin-4-one.

In the title compound, C(18)H(13)ClN(2)OS, the thia-zolidinone ring is slightly distorted and adopts a envelope conformation. The basal plane is nearly perpendicular to the quinoline ring, forming a dihedral angle of 86.1 (1)°, and makes a dihedral angle of 14.9 (1)° to the benzene ring. The benzene ring is also nearly perpendicular to the quinoline ring, forming a dihedral angle of 89.4 (1)°. In the crystal, non-classical C-H⋯O and C-H⋯N hydrogen bonds link the mol-ecules, forming polymers along b.

Photoinduced three-component reactions of tetracyanobenzene with alkenes in the presence of 1,3-dicarbonyl compounds as nucleophiles.

Photoinduced three-component reactions between tetracyanobenzene (TCNB), an aromatic olefin, and a beta-dicarbonyl compound afford products composed of the three components via formal elimination of hydrogen cyanide, leading to the vicinal dialkylation of the olefin and the alpha-alkylation of the beta-dicarbonyl compounds. It is shown that these reactions are initiated by photoinduced electron transfer (PET) from the olefin to the singlet excited TCNB and proceed by a nucleophile-olefin combination, aromatic substitution (NOCAS) reaction sequence with the enolized beta-dicarbonyl compound as a nucleophile. Therefore, aromatic olefins are suitable substrates in photo-NOCAS reactions when TCNB is used as the electron acceptor. In addition, these results show that the enol of beta-dicarbonyl compound serves as a carbon nucleophile to trap the alkene cation radical in PET reactions to lead to C-C bond formation.

Adaptability comparison of E. fetida in vermicomposting against sludge from livestock wastewater treatment plant based on their several growth stages.

Vermicomposting is a low-cost, eco-efficient process to deal with organic wastes. Mixtures of swine manure (SM), cow dung (CD), and animal wastewater treatment plant sludge (S) were applied as feeds, and Eisenia fetida was employed in this study to investigate the vermicomposting efficiency based on their several growth stages. The hatching test resulted in a 100 % hatching rate in S60SM40 (60 % S + 40 % SM) mixture, while 4.40 hatchlings per cocoon were observed. The growth of infancy performed best in 0-20 % CD mixtures (0.05 ± 0.002 g), followed by in SM + CD (0.04 ± 0.003 g). The highest growth rate of young and adult E. fetida was noticed in CD + S mixtures (11.14 ± 0.01 and 6.00 ± 0.02 mg/d/worm, respectively), while the higher cocoon production of adults was noticed in S + SM mixtures especially in S40SM60 (537 ± 5 worms). Moreover, the conversion of solids; the modified pH value; the reduction in total organic carbon (TOC); total Kjeldahl nitrogen (TKN), NH4-N, NO3-N, and C:N ratio; and the rich in total available phosphorus (TAP) and total potassium (TK) content by young and adult E. fetida were related to the growth of worms. Such work would benefit understanding and to increase the efficiency of vermicompost processing of different wastes.

Metal-free tandem oxidative C(sp(3))-H bond functionalization of alkanes and dearomatization of N-phenyl-cinnamamides: access to alkylated 1-azaspiro[4.5]decanes.

The TBPB promoted tandem oxidative C(sp(3))-H bond functionalization of simple alkanes/alkylation-initiated dearomatization of N-phenyl-cinnamamides is reported, providing a direct method for the synthesis of alkylated 1-azaspiro[4.5]decanes with excellent regioselectivity and diastereoselectivity. The formation of two C(sp(3))-C(sp(3)) bonds and construction of a spirodienone motif are involved in one step.