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The mechanism of the combined action of the C–CO2and C–H2O reactions has yet to be clarified in the study of oxy-fuel combustion with wet flue gas recirculation (WFGR). The ultrahigh temperature (1573 K) and atmosphere of an industrial boiler are simulated in the flat flame burner reaction system (FFB-RS). The measurement of surface reactive groups and combustion reactivity of char uses Fourier transform infrared spectroscopy (FTIR) and a microfluidized bed reaction analyzer (MFBRA). The results show that char combustion reactivity has an excellent positive correlation with an O-containing reactive group. Above a 35% H2O concentration, its physical properties dominate, while below 35%, its chemical properties play a significant role. When the ratio of H2O/CO2is close to 1, there is a synergistic relationship between the C–CO2and C–H2O reactions, which did not occupy the same active sites, promoting the formation of O-containing reactive groups (33.83%) and alkyl complexes (19.6%) with a combustion reaction rate of 0.225%/s.

Paclitaxel (Taxol@) as a cornerstone of chemotherapy remains in high demand. The semi-synthesis of paclitaxel viacoupling of Taxus leaf-produced baccatin III and manually synthesized isoserine (C-13 side chain) is one of the solutions to avoid environmental damage caused by the sacrifice of the whole Taxus brevifolia. A green synthesis of the C-13 side chain is pivotal to the green production of paclitaxel. We herein report a green synthesis of isoserine derivatives and the semi-synthesis of paclitaxel viaa straightforward assembly of isoserines based on an Rh2(TPA)3(OAc)/CPA1 co-catalyzed asymmetric multi-component reaction of ethyl diazoacetate, triethyl silanol and N-(anthrancen-9-ylmethyl)benzaldimine. The method is featured by improved atom economy, effective mass yield, and environmental factors compared to our previous racemic method and BMS company's semi-synthesis method. And the method allows for rapid access to paclitaxel derivatives with varied C-13 side chains.

This article proposes that the problem of pastoral irony (as formulated in Harry Berger’s seminal article on strong and weak pastoral) and the nature of ekphrasis are both clarified if they are understood as expressions of the desire for an escape from meaningful, signifying language and into the materiality of objects. Drawing on responses to Theocritus, readings of ekphrasis, and philosophical interpretations of the boundary between words and things, I argue that pastoral irony represents an initial moment of escape from signification, and ekphrasis a final moment of representing objects, mediated by a paradoxical object representing the negation of meaning.

The blockade of A2Aadenosine receptor (A2AAR) activates immunostimulatory response through regulating signaling in tumor microenvironment. Thus, A2AAR has been proposed as a promising target for cancer immunotherapy. In this work, we designed a new series of benzo[4,5]imidazo[1,2-a]pyrazin-1-amine derivatives bearing an amide substitution at 3-position to obtain potent antitumor antagonist in vivo. The structure–activity relationship studies were performed by molecular modeling and radioactive assay. The in vitroanticancer activities were evaluated by 3′,5′-cyclic adenosine monophosphate (cAMP) functional and T cell activation assay. The most potent compound 12o·2HClshowed much higher affinity toward A2AAR (Ki= 0.08 nM) and exhibited more significant in vitroimmunostimulatory anticancer activity than clinical antagonist AZD4635. More importantly, 12o·2HClsignificantly inhibited the growth of triple-negative breast cancer by reversing immunosuppressive tumor microenvironment in the xenograft mouse model without severe toxicity at the testing dose. These results make 12o·2HCla promising immunotherapy anticancer drug candidate.

We herein reported a sustainable synthesis of 3,3-disubstituted oxindoles viaa Michael-type reaction based on the CuBr-catalysed capture of carboxylic oxonium ylides with isatylidene malononitrile. The reaction is characterized by a high atom economy and low economic constraints. The catalyst CuBr could be conveniently recyclized. The products of the reaction were found to be inhibitory against Na ion channels. We expect the reaction to shed the light on synthesis of biologically interesting molecules directed by principles of green chemistry.

•Crystallization kinetic properties of ammonium bicarbonate in binary mixed solvents.•The nucleation rate is most directly promoted by an increase in supersaturation.•Stirring rate has both positive and negative effects on the crystal growth process.•The effect of high drop acceleration rate of lysate on nucleation rate is significant.•The diffusion of solute is accelerated by the action of static magnetic field.

In pedestrian traffic, individuals’ behaviors at crossings are significantly influenced by their mentality. In this paper, we consider the spread of anxiety among pedestrians, based on SIS model. The evolutionary game dynamics model of pedestrian crossing strategy is established on the complex network, and the evolutionary mechanism of pedestrian crossing strategy selection and the control strategy of anxiety are analyzed. The results show that individuals can effectively control the spread of anxiety when choosing waiting strategies, which shows that improving pedestrian safety awareness can effectively reduce pedestrian–vehicle conflict when crossing the street. Moreover, introducing the third-party reward mechanism can effectively enhance the effect of waiting behavior.

N-(Anthrancen-9-ylmethyl) isoserines are useful drug intermediates but short for efficient synthesis. We herein report the synthesis of N-(anthrancen-9-ylmethyl) isoserines via a Rh2(Ph3COO)3(OAc) and chiral phosphoric acid (CPA) synergistically catalyzed multicomponent reaction (MCR) of N-alkyl imines, alcohols, and diazoesters. The method representing the first example of N-alkyl imines-involved MCR is featured by high atom-economy, high diastereo- and enantioselectivities, and broad substrate scope. DFT calculations on the mechanism of the MCR reveals that the hydrophobic interactions and π–π stackings between N-(anthrancen-9-ylmethyl) imines and Rh2(Ph3COO)3(OAc)/CPA cocatalyst is essential to the reactivity and stereocontrol. The synthetic applications of the MCR products include the semisynthesis of paclitaxel, its alkyne-tagged derivative, and β-lactam as an anticancer agent overcoming paclitaxel-resistance. We expect this work to shed light on the development of new N-alkyl imines-involved reactions and on the synthesis of drugs with isoserines as intermediates.

All reactions with Seebach′s nitropropene (II) proceed with complete cis‐fused selectivity.