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Various 2-aminobenzophenones were synthesized from readily available 2-arylindoles in DMSO under O2 balloon atmosphere. The synthesis was carried out without the aid of a transition metal catalyst or moisture-sensitive organometallic reagents from 2-arylindoles.

Various dihydrobenzo[c]azepines were synthesized in good yields via Pictet–Spengler cyclization protocol from tosylamide derivatives of Morita–Baylis–Hillman adducts and 1,3,5-trioxane. The synthesis was carried out in the presence of easily removable montmorillonite K-10 in short time in high yields.

A transition metal and base-free synthesis of 3,3-diaryl-2-oxindoles has been developed from 2,2,N-triarylacetamides in the presence of montmorillonite K-10 in 1,2-dichlorobenzene under O2 balloon atmosphere.

Various spirofluorenyl oxindoles and spiroindeno[1,2- b ]indolyl oxindoles were synthesized in good yields in one-pot reaction by TiCl 4 -catalyzed sequential inter- and intramolecular Friedel–Crafts reactions of isatins with meta -arylphenols and 2-arylindoles in 1,2-dichloroethane.

Various 3-(γ,δ-disubstituted)allylidene-2-oxindoles were synthesized by the Wittig reaction between isatins and the phosphorous ylide derived in situ from the Morita–Baylis–Hillman bromides. The 3-allylidene-2-oxindole could be used as an efficient synthetic precursor of 1-thiacarbazole derivatives. During the conversion of 2-oxindole moiety to 2-thiooxindole by Lawesson's reagent, 1-thiacarbazole derivative was obtained in good yield.

The synthesis of pyrazolo[4,3-c]quinolines has been carried out from the Morita–Baylis–Hillman bromides of 2-bromobenzaldehydes and methyl vinyl ketone. The synthesis involved a novel one-pot preparation of functionalized pyrazoles from α,β-enones, a one-pot Cu-mediated intramolecular N-arylation, and the elimination of p-toluenesulfinic acid.

Various pyrazolo[1,5-a]quinolines were synthesized via the intramolecular Friedel-Crafts reaction of 1-aryl-5-styrylpyrazoles and the following base-catalyzed aerobic oxidation process. The required 1-aryl-5-styrylpyrazoles were readily prepared from the corresponding conjugated dienones and arylhydrazines in a one-pot process.

The title compounds (III) are obtained by efficient one-pot synthesis from α,β-enones and arylhydrazine hydrochlorides.

In spite of their potential as biologically active compounds, the high molecular mass and viscous natures of fucoidans have hampered their applications especially as a therapeutic agent. Herein the fucoidan-degrading enzyme activities were partially purified from the cultured cells of Sphingomonas paucimobilis PF-1 mainly by ammonium sulfate precipitation. This enzyme preparation degraded fucoidans from the Korean Undaria pinnatifida sporophyll into several low-molecular weight fuco-oligosaccharides (LMFOs) with less than 3,749 Da. The FTIR spectra of intact fucoidan and mixture of LMFOs (1,389-3,749 Da) showed no significant structural difference except for about 10% reduced level of sulfate esters in LMFOs. The LMFOs have exerted strong anticoagulating activities at which the activated partial thromboplastin time (APTT) and thrombin time (TT) were significantly prolonged, although 3 approximately 20 times weaker activities were observed than those of intact fucoidan. In addition, unlike intact fucoidan, LMFOs did not affect significantly to the prothrombin time (PT). These results suggest that the partially purified fucoidan-degrading enzyme preparation is valuable for the production of fuco-oligosaccharides having anticoagulating activities, and that the molecular weight and/or sulfate content of the fucoidan from the Korean Undaria pinnatifida sporophyll could be important factors for its anticoagulating activity.