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A new kind of photolabile protecting group (PLPG) for carboxyl moieties was designed and synthesized as the linker between resin and peptide. This group can be used for the protection of amino acid carboxyl groups. The peptide was synthesized on Nph (2‐hydroxy‐3‐(2‐nitrophenyl)‐heptanoic acid)‐derivatized resins and could be cleaved under UV exposure, thus avoiding the necessity for harsh acid‐mediated resin cleavage. The PLPG has been successfully used for solid‐phase synthesis of peptides., A photolabile protecting group (PLPG) for carboxyl derivatives was designed and synthesized. The newly derived molecule can be used for the protection of amino acid carboxyl groups and can be removed rapidly under the condition of 365 nm.

Coumarin moiety has garnered momentous attention especially in the design of compounds with significant biological activities. In this work, a series of 3-substituted coumarin derivatives 6a-6l were synthesized and fully characterized. Most of the compounds could obviously inhibit the activity of cyclooxygenase-1 (COX-1) at the concentration of 10 µM. Besides, 6h and 6l exhibited highest inhibitory effects against COX-2 with inhibition rates of 33.48 and 35.71%, respectively. Detailed structure-activity relationships (SARs) were also discussed. In vivo studies, 6b, 6i and 6l could remarkably repress the xylene-induced ear swelling in mice at the dose of 20 mg/kg. Especially, 6l seemed to be the most effective compound at the dose of 10 mg/kg, displaying favorable anti-inflammatory activity comparable to indomethacin. All of these findings suggested that 6l might be utilized as a candidate for the treatment of inflammatory diseases.

Three new types of heterogeneous catalysts were prepared using a facile approach by the immobilization of Grubbs catalysts on PEGylated Merrifield resin. One of the immobilized catalysts was more efficient than the free catalyst for the metathesis of leaf alcohols in conversion and selectivity and was reused repeatedly (up to 5 cycles) with only a slight loss of activity (10.5 %). The long‐chain PEGylated linker provided an appropriate distance between the resin and the catalytic center so that the ruthenium catalysts acted as the free catalyst.

Given that C-glucosylisoflavones often possess promising biological activities, the development of an efficient synthetic method for this type of molecules is useful for drug discovery. Accordingly, a highly efficient five-step strategy was developed for the total synthesis of puerarin, an isoflavone C-glycoside. An alkyl substituent 4-CH3OC6H4CH2CH2 with an electron-donating group on the aromatic ring was used to enhance the reactivity of phenol and the regioselectivity of O-C rearrangement of phenol glycoside. Thus, coupling of the ethylbenzene derivative of a phenol 1c with glycosyl trifluoroacetimidate 2 resulted in C-glycoside 3c in a 46.2% yield, which was easily de-tert-butylated with trifluoroacetic acid and oxidized with 2,3-dicyano-5,6-dichlorobenzoquinone to produce deoxybenzoin 5. The ring closure reaction of 5 followed by deprotection gave puerarin. This new synthetic strategy is also suitable for the total synthesis of other C-glucosylisoflavones.

In this work, a series of novel benzyl naphthyl sulfoxides (sulfones) derived from Ex-RAD were designed and synthesized as potential radioprotective agents. Some of the compounds considerably protected HUVECs against 60Co γ-irradiation, accompanied by the absence of cytotoxicity. Compared to Ex-RAD, compound 8n not only exhibited a significant protective effect on cell survival and radiation-induced DNA damage, but also remarkably enhanced the survival (100%) of mice in 30 days after being exposed to irradiation. The results suggested that some target compounds are valuable for further research as promising radioprotectors.

The total synthesis of two isoflavone C-glycosides (6-tert-butylpuerarin and 6-tert-butyl-4′-methoxypuerarin) was achieved through the deoxybenzoin pathway with overall yields of 14.6% and 14.2%. The key intermediate 12 was obtained by de-tert-butylation of 10 with trifluoroacetic acid and Friedel-Crafts acetylation of 2-C-β- d -glucopyranoside 11. The ring closure of 12 with the POCl3/DMF reagent resulted glucosyl isoflavone formation 13, which was debenzylated and demethylated by BBr3 to obtain 14 and 15. This pathway represents a novel synthetic pathway based on Friedel-Crafts acetylation and Vilsmeier-Haack cyclization to achieve isoflavone C-glycosides in high yields.

The first total synthesis of an isoflavone C-glycoside (6-tert-butylpuerarin) using commercially available 4,6-di-tert-butylbenzene-1,3-diol as starting material was achieved in five steps with an overall yield of 2.8%. The key intermediate 4 was obtained by de-tert-butylation of 2 with trifluoroacetic acid and Friedel-Crafts acetylation of 2-C-β-D-glucopyranoside 3. Condensation of 4 with 4-(benzyloxy)benzaldehyde resulted in the formation of C-glucosylchalcone 5, which was cyclized by oxidative rearrangement using (diacetoxyiodo)benzene (DIB) and p-toluenesulfonic acid to obtain the target molecule 6. This environmentally friendly and concise synthetic pathway should be applicable to the large-scale synthesis of various isoflavone C-glycosides.