Catalytic Asymmetric Decarboxylative Michael Addition To Construct an All-Carbon Quaternary Center with 3-Alkenyl-oxindoles.

The first highly enantioselective asymmetric decarboxylative addition of ß-keto acids with 3-alkenyl-oxindoles bearing an all-carbon quaternary stereocenter have been developed. The relevant products were acquired in 49-98% yields with 88-98% enantioselectivities in the presence of 0.04-1.0 mol % of chiral rhodium catalyst. The comprehensive practicability of this method was proven in the preparation of the key intermediate, which can be easily transformed into analogues of physovenine and physostigmine.

The impact of COVID-19 on business perspectives of sustainable development and corporate social responsibility in China.

The new coronavirus (COVID-19) has generated an unprecedented degree of social and economic impact on the planet, but few researchers have explored the repercussion of COVID-19 for sustainable development (SD) and corporate social responsibility (CSR), especially from the perspective of Chinese businesses. This paper is the first to outline the priority changes of both SD and CSR over the period of COVID-19 incidence in China. An online questionnaire survey of 1161 owners and managers of Chinese companies was conducted, and respondents were asked to score the priorities of their company over the pre, during and post COVID-19 periods. The research was carried out at the end of the first COVID-19 wave in China but during the period of lockdown in some parts of the country. It was found that there was a priority change regarding three dimensions of sustainable development and 13 aspects of CSR. While the social dimension of SD was prioritized during and post COVID-19, the environmental dimension was the only one deemed to be less important and less prioritized over the longer term after the pandemic. The top three short-term CSR priorities were having in place a workplace health and safety plan, engaging in philanthropic activities and protecting biodiversity, and the top three longer-term CSR priorities were job creation, protecting biodiversity and having in place a workplace health and safety plan. Environmental protection and using clean energy were not reported as a CSR priority. The paper concludes that China's recovery mode cannot be called 'green' and suggests ways this could be changed.

An N-heterocyclic carbene-catalyzed switchable reaction of 9-(trimethylsilyl)fluorene and aldehydes: chemoselective synthesis of dibenzofulvenes and fluorenyl alcohols.

An N-heterocyclic carbene-catalyzed synthesis of dibenzofulvenes and fluorenyl alcohols was developed. In the presence of 10 mol% NHC (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and 4 Å molecular sieves, 9-(trimethylsilyl)fluorene undergoes an olefination reaction with aldehydes to produce dibenzofulvenes in 43-99% yields. However, on reducing the NHC loading to 1 mol% and with the addition of water, 9-(trimethylsilyl)fluorene selectively undergoes nucleophilic addition with aldehydes to afford fluorenyl alcohols in 40-95% yields.

Janus Particles Templated by Janus Emulsions and Application as a Pickering Emulsifier.

One-step vibrational mixing has afforded the batch-scale preparation of a Janus emulsion. The fabrication of Janus particles (JPs) templated by Janus emulsions was motivated by the topology and composition of the Janus droplets being highly tunable and controllable. Two immiscible polymerizable monomers were introduced as inner phases of the Janus emulsion. The advanced geometry of the resultant JPs was easily and precisely controlled from "snowman" to "dumbbell" by adjusting the mass ratio of two oils in the initial emulsion. The surface coverage of one lobe to the other was tuned by adjusting the mass ratio of mixed surfactants. Moreover, the size of JPs was able to be extended continuously from hundreds of micrometers to a few hundred nanometers while their morphologies remained within this wide size range. The proposed strategy is a universal technique in the synthesis of a family of composite polymeric JPs with both chemical and shape anisotropy. In addition, the as-generated chemically biphasic JPs were applied as emulsifiers to stabilize Pickering emulsions, and more attractively, emulsion inversion was readily achieved by choosing JPs with different morphologies.

Anisotropic particles templated by Janus emulsion.

Anisotropic particles, with morphology from crescent to moon shape and size from micrometer to nanometer scale, are fabricated in batch scale with Janus emulsion as template. The strategy is also useful in the synthesis of Janus particles with chemically distinct hemispheres.

Droplet topology control of Janus emulsion prepared in one-step high energy mixing.

Droplet topology of a Janus emulsion in a vegetable oil (VO)/silicone oil (SO)/Tween 80 aqueous solution (Aq) system prepared in a one-step high energy mixing was investigated, mainly by image observation. Quantitative information of the topology was analyzed referring to the curvature of VO/SO interface, the location of contact plane, and the volume ratio of VO/SO within individual droplets. The results show that the "stable Janus emulsion" region in the phase map enlarges with surfactant concentration. The average volume ratio of two oil lobes within an individual Janus droplet agrees with the emulsion composition in the "stable Janus emulsion" region, which means that the droplet topology can be controlled by the emulsion preparation process within realistic limits. The volume ratio of VO/SO within individual droplet ranges from about 0.54 to 0.17 in the VO/SO/3 wt% Tween 80(Aq) system, beyond which separate VO and SO droplets are observed. The topology of a Janus droplet is found to be determined by both the contact angle of three liquids in the contact line and the location of the contact plane. The contact angle of the oil cap is determined by the interfacial tension referring to the local equilibrium. The location of the contact plane is the dominant factor determining the volume ratio of two oil lobes. Composition change in the emulsion results in the corresponding tune of the location of contact plane and subsequently, the volume ratio of two oils within Janus droplets.

Janus emulsions formed with a polymerizable monomer, silicone oil, and Tween 80 aqueous solution.

Janus emulsions of a polymerizable monomer tripropyleneglycol diacrylate (TP) combined with silicone oil (SO) as inner oil phases and Tween 80 aqueous solution as continuous phase are prepared in a one-step high energy mixing process. The dependence of droplet topology on the concentration of surfactant, TP/SO ratio, and the stirring speed during emulsification is investigated. The result shows that the volume ratio of two oils within an individual droplet changes correspondingly to the total composition of emulsion. Increasing the speed of stirring results in a significant reduction in the droplet size, i.e. a five times increase in the stirring speed produces a droplet size reduction from hundreds to a few microns. What is more important, the topology of Janus drops remains similar for the different preparations. These fundamental investigations illustrate the potential for future Janus particle synthesis in batch scale with a controllable particle topology.

Ultrastructural study of nuclear inclusions immunohistochemically positive for surfactant protein A in pulmonary adenocarcinoma with special reference to their morphogenesis.

To investigate the fine-structural nature of nuclear inclusions immunopositive for surfactant protein A (SP-A) antibody staining, a detailed ultrastructural study was performed, as well as immunohistochemical examination of pulmonary adenocarcinomas. Surgically resected tumor specimens from 31 patients were examined by immunohistochemistry focused on reactivity to SP-A and thyroid transcription factor 1 (TTF-1) antibodies. Only cases with >5% positive nuclear inclusions in cancer cells were considered positive, some of which were examined by electron microscopy. Immunohistochemically, 6 of 31 cases were doubly positive for SP-A and TTF-1 antibodies. On electron microscopy, SP-A-positive nuclei contained diffuse or globular fine granular substance as inclusions. Both types of globular and diffuse inclusions were sometimes connected to the inner nuclear membrane, in association with fragmented or stacked membranous structures. The findings of this study suggested that nuclear inclusions positive for SP-A antibody staining in adenocarcinomas of the lung were derived from accumulated content in the perinuclear cistern resembling pseudoinclusion processes and composed of proteins antigenically cross-reactive with SP-A.

Effect of carbonic anhydrase-related protein VIII expression on lung adenocarcinoma cell growth.

Carbonic anhydrase-related protein VIII (CA-RP VIII) is expressed in most non-small cell lung cancer, and especially strongly at the front of tumor progression. Screening analysis of CA-RP VIII expression in a panel of cultured lung cancer cell lines showed that a well differentiated adenocarcinoma cell line, PC-9, appeared to lack CA-RP VIII. Subsequently, CA8 cDNA was transfected with an expression vector into PC-9. Ectopic overexpression of CA-RP VIII reduced the growth of PC-9 cells on uncoated culture dishes, especially when the cultures were started at low cell density, but increased cell growth on laminin-coated dishes. Interestingly, ectopic CA-RP VIII expression markedly reduced caspase-3 activity induced by serum starvation and anti-cancer agents in PC-9 cells. The present findings suggest that CA-RP VIII expression promotes progression of lung cancer by multifarious mechanisms.