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In this study, a rapid prototyping method for droplet generators using pipette tips and glass capillaries (pipette-tip-shelled capillary microfluidic device (PiT-CMD)) is described. The proposed de...

We present droplet manipulation using a digital microfluidic device comprising downward electrodes. Using this device, we demonstrated droplet transportation, programmable dispensing, and droplet c...

This paper describes the performance of organic droplet mixing using a digital microfluidic (DMF) device. DMF devices have been applied to the dispensation and transportation of aqueous droplets us...

Microchannels used for high-precision handling of small amounts of liquids are employed in various fields. However, technical limitations with respect to complex channel structure fabrication exist...

This paper describes a novel method for preparing core–shell structures from droplets. The core–shell structures are formed via water transfer from a droplet of polymer solution to a high-osmotic-p...

A concise total synthesis of the 11-membered cyclic (+)-aspercyclide C is reported. Key to success was the fine-tuning of the reaction media to realize an oxidative, macrocyclic diaryl C–O bond for...

The total synthesis of gravicycle, isolated from Grevillea robusta, has been achieved for the first time. The key step of our synthetic process is the efficient assembly of a highly functionalized ...

Cross-conjugated 5-methylene-3-heptene-1,6-diyne derivatives have been proved to be readily epoxidized by molecular oxygen.

An adduct formed from 2-trichlorostannyl-3-pentanone and phenylethynyltrichlorotin was isolated, and the structure was determined by spectroscopy and X-ray crystallography. It provides a direct evidence for the carbostannylation of alkynyl metals.

Azadiradione, a limonoid isolated from the neem plant, possesses a unique stereostructure distinct from that of the steroids. We describe a concise synthesis of the tetracyclic framework of azadira...

Ciguatoxins, principal causative toxins of ciguatera seafood poisoning, are large ladder-like polycyclic ethers that exert their toxicities by binding to the voltage-sensitive sodium channels. We r...

Asymmetric cycloaddition of 1-phenoxycarbonyl- (1) or 1-methoxycarbonyl-1,2-dihydropyridine (2) with N-acryloyl-(1S)-2,10-camphorsultam (3) produced chiral isoquinuclidine 4a or 5a in good yields w...

A highly stereoselective method for glycosylation of tertiary alcohols with the amino sugar moiety of C-1027 chromophore was developed.

The β-tyrosine moiety of C-1027 chromophore (1) was enantioselectively synthesized and efficiently coupled with propargylic epoxide (2) using CsF.

Treatment of 2,2-dimethyl-6-nonene-4,8-diynal (2) with CeCl3/LiN(TMS)2 at −5∼25°C gave 2,2-dimethyl-1-indanol (3) in a moderate yield. In the present study, acyclic (Z)-enediyne aldehyde (2) was cyclized to afford a nine-membered monocyclic enediyne (7), which cycloaromatized spontaneously at room temperature.

Recognition of the helicity of 1,12-dimethylbenzo[c]-phenanthrene-5,8-dicarboxylic acid (1) by cyclodextrins (CDxs) has been studied by means of 1H NMR spectroscopy. The binding constant (K) for the (M)-1-β-CDx complex is 18700±1700 dm3 mol−1 which is much larger than that of the (P)-1-β-CDx complex (2200±100 dm3 mol−1). The results sugget the formation of the hydrogen bonds between the CO2− groups of 1 and the OH groups of twisted β-CDx in water.

Unstable 3,5,7,9-octatetrayn-2-ol showed potent antimicrobial activity against bacteria and fungi. Its trimethylsilyl derivative, which possessed much improved stability, showed comparable activity. It is due to desilylation under neutral aqueous conditions.

Alkynyldichlorogalliums dimerize in hydrocarbon solvents via carbogallation giving 1,1-dimetallo-1-buten-3-yne derivatives.

Poly[4-(t-butyldimethylsilyloxy)-2-trimethylsilylphenylacetylene] and poly[5-ethynyl-3-(t-butyldimethylsilyloxy)phenyl (R)-2-phenylpropionate] were desilylated with Bu4NF in THF. The solution changed its color depending on the structure of the aromatic pendants.

Deeply colored soluble polyacetylenes were synthesized from 1-ethynylnaphthalene and 3,6-dibutyl-9-ethynylphenanthrene by employing a tungsten (IV) catalyst. Since 2-ethynylnaphthalene gave the less conjugated polymer, connection mode of the aromatic pendants was found to be essential for maintaining the conjugated structure of the polyene chain. Electrochromic properties of poly(1-ethynylnaphthalene) were also studied.

Thiele type acylation reaction of p-tropoquinone 1, a novel nonbenzenoid quinone, in the presence of sulfuric acid, resulted in the unexpected ring contraction to a benzaldehyde derivative 2, in addition to a tropone 3. It was proved in this reaction that acetoxyl group attacked C3 exclusively and that the carbon became aldehydic. In the reaction catalyzed by BF3, regioselectivity of the nucleophilic attack was reduced to 4:1 (C3:C4) yielding 9, 10, and 11, all seven-membered ring compounds. Plausible mechanisms for the all reaction pathways are proposed.