Pd-catalyzed sequential reaction for the synthesis of fused tricyclic compounds containing a dihydrofuran or isobenzofuranone unit

A novel Pd-catalyzed sequential reaction for the synthesis of fused tricyclic compounds with a dihydrofuran or isobenzofuranone unit was developed.

Regio- and stereo-selective synthesis of multi-substituted 3-pyrrolines

多代替的 3-pyrrolines 的 regio 选择、立体声选择的合成被开发了。多代替的 3-pyrrolines 被压克力与 azomethine ylides 吃了的甲基 2-(phenylselanyl ) 的 1,3-dipolar 出租机动三轮车增加在好收益综合，由 N-acylation 和 oxidation&#x2013 列在后面； phenylseleno 的消除组。

Comparison of enhancement techniques based on neural networks for attenuated voice signal captured by flexible vibration sensors on throats

Wearable flexible sensors attached on the neck have been developed to measure the vibration of vocal cords during speech.However,highfrequency attenuation caused by the frequency response of the flexible sensors and absorption of high-frequency sound by the skin are obstacles to the practical application of these sensors in speech capture based on bone conduction.In this paper,speech enhancement techniques for enhancing the intelligibility of sensor signals are developed and compared.Four kinds of speech enhancement algorithms based on a fully connected neural network(FCNN),a long short-term memory(LSTM),a bidirectional long short-term memory(BLSTM),and a convolutional-recurrent neural network(CRNN)are adopted to enhance the sensor signals,and their performance after deployment on four kinds of edge and cloud platforms is also investigated.Experimental results show that the BLSTM performs best in improving speech quality,but is poorest with regard to hardware deployment.It improves short-time objective intelligibility(STOI)by 0.18 to nearly 0.80,which corresponds to a good intelligibility level,but it introduces latency as well as being a large model.The CRNN,which improves STOI to about 0.75,ranks second among the four neural networks.It is also the only model that is able to achieves real-time processing with all four hardware platforms,demonstrating its great potential for deployment on mobile platforms.To the best of our knowledge,this is one of the first trials to systematically and specifically develop processing techniques for bone-conduction speed signals captured by flexible sensors.The results demonstrate the possibility of realizing a wearable lightweight speech collection system based on flexible vibration sensors and real-time speech enhancement to compensate for high-frequency attenuation.

Solid Phase Synthesis of 1,4-Disubstituted 1,2,3-Triazole from Polystyrene-supported Selenium Resin

We report here a solid-phase synthesis of 1, 4-disubstituted 1, 2, 3-triazole using polystyrene-supported selenium resin. The resin used here not only works as a simple linker, but also assists the crucial α-alkylation reaction and selenoxide syn-elimimation, which ensures the purity of the products.

Polymer-support Selenium-induced Electrophilic Cyclization:Solid-phase Synthesis of Flavonoids

The Lewis acid mediated polystyrene supported selenium cyclization of chalcones and oxidative cleavage of selenium resins flavonoids in good yields and purities have been reported. induced intramolecular gave the corresponding

The facile insertion of β-keto sulfones to arynes:The direct preparation of polysubstituted ortho-keto benzyl sulfones

One novel carbon-carbon bond insertion reaction of arynes has been developed. By this reaction β-keto sulfones can insert the triple bond of arynes to prepare polysubstituted ortho-keto benzyl sulfones.

Solid Phase Synthesis of 4(1H)Quinolones from Resin-Bound Cyclic Malonic Ester

The solid phase synthesis of 4 (1H) quinolones has been reported.

A Facile Synthesis of α-Phenylthio-α, β-Unsatuated Esters

a-Phenylthio-a, b-unsaturated esters 6 were synthesized by Witting reaction of 3, which were prepared by a phenylsulfenyllation-trans-ylidation reaction.

Solid-phase synthesis of (Z)-allyl iodides from 3-acetoxy-2-methylene-alkanoates with recyclable polymer-supported selenium bromide

Reaction of polystyrene-supported lithium selenide with 3-acetoxy-2-methylene-alkanoates afforded the corresponding allyl selenide resins and subsequent cleavage from the polymer by treating with methyl iodide to furnish （Z）-allyl iodides in good yields and high purities. The polymeric selenium reagent can be regenerated and reused. So it is a environmentally benign reagent.

Traceless solid-phase synthesis of 3-substituted isoxazoles from polystyrene-supported vinyl selenide

A novel facile procedure for traceless solid-phase synthesis of 3-substituted isoxazoles in good yields and with excellent purities using polymer-supported vinyl selenide has been developed.

Arylation of Allyl, Cinnamyl and Propargyl Bromide with Triarylbismuth Catalyed by Pd(0)

Allyl and cinnamyl and propargyl bromide reacted under mild conditions with triarylbismuth under catalysis by Pd(O) to give 3-arylpropenes, 1, 3-diarylpropenes and arylpropadienes in modest to excellent yields.

Solid Phase Synthesis of 4H-Pyrimido[2,1-b] Benzothiazol-4-ones from Resin-Bound Cyclic Malonic Ester

The solid phase synthesis of 4H-pyrimido[2,1-b] benzothiazol-4-ones has been reported.

Polystyrene-supported Benzyl Selenide: An Efficient Reagent for Highly Stereocontrolled Synthesis of Substituted Olefins

Polystyrene-supported benzyl selenide has been prepared. This novel reagent was treated with LDA to produce a selenium stabilized carbanion, which reacted with alkyl halide, followed by selenoxide syn-elimination, to give substituted olefins stereospecificly.

A New and Effective Synthesis of Terminal Alkylselenylacetylenes

The terminal alkylselenylacetylenes (RSe-C = C-H) 3a-h were prepared by the reaction of ethynylmagnesium bromide at -20 degrees C in THF with alkylselenyl bromides derived from dialkyl diselenides and bromide.

FACILE AND HIGHLY STEREOSELECTIVE SYNTHESIS OF （2Z）－α－PHENYLSELENO－α，β－UNSATURATED KETONES

?Phenylseleno-α-acylmethylene triphenylarsoranes(3) were synthesized by reacting α-acylarsonium ylides(1) with phenylselenenyl iodide.The α-seleno arsonium ylides(3 ) nave sufficient activity to carry out Wittig type reaction, affording the first method for the stereoselective synthesis of (2Z) -α-phenylseleno-α,β-unsaturated Ketones(6 ).

A micro-nano optogenetic system based on probiotics for in situ host metabolism regulation

Genetically engineered bacteria have aroused attention as micro-nano drug delivery systems in situ.However,conventional designs of engineered bacteria usually function constantly or autonomously,which might be non-specific or imprecise.Therefore,designing and optimizing in situ control strategy are important methodological progress for therapeutic researches of intestinal engineered bacteria.Here,a micro-nano optogenetic system based on probiotic was developed combining microelectronics,nanotechnology,and synthetic biology to achieve in situ controllable drug delivery.Firstly,optogenetic engineered Lactococcus lactis was orally administrated in the intestinal tract.A wearable optical device was designed to control optical signals remotely.Then,L.lactis could be customized to secrete peptides according to optical signals.As an example,optogenetic L.lactis system can be constructed to secrete glucagon-like peptide-1(GLP-1)under the control of the wearable optical device to regulate metabolism.To improve the half-life of GLP-1 in vivo,Fc-domain fused GLP-1 was optimally used.Using this strategy,blood glucose,weight,and other features were well controlled in rats and mice models.Furthermore,upconversion microcapsules were introduced to increase the excitation wavelength of the optogenetic system for better penetrability.This strategy has biomedical potential to expand the toolbox for intestinal engineered bacteria.