A series of sulfenimine cephalosporin sulfoxide derivatives (7a–v) were designed, synthesized and evaluated for their inhibitory activity against TEM-1 and cephalosporinase in cell-free systems. Some of the tested compounds showed enhanced inhibitory activity against class C β-lactamase cephalosporinase compared with the tazobactam. The most promising compounds 7c and 7n (IC50 = 7.6 and 8.6 μmol/L, respectively) were further investigated in combination with cefradine against a variety of clinical isolated β-lactamase-producing bacterial strains.A series of novel sulfenimine cephalosporin sulfoxides were prepared and identified as potent β-lactamase inhibitors. Some of the compounds showed potent inhibitory activity against the class C β-lactamase cephalosporinase.

A series of sulfenimine cephalosporin derivatives(6a—6t) was designed, synthesized and evaluated for their inhibitory activity against class A β-lactamase(TEM-1) derived from E. coli, and class C β-lactamase (cephalosporinase) derived from wild Bacillus subtilis in cell-free systems. Most of the tested compounds showed enhanced inhibitory activity against class C β-lactamase(cephalosporinase) compared with tazobactam. The most promising compounds 6c and 6o in combination with cefradine(IC50=1.80 and 1.59 μmol/L, respectively) were further investigated against a series of clinical isolated β-lactamase-producing bacterial strains. The results reveal that compounds 6c and 6o in combination with cefradine show two to four times more activity than cefradine alone against methicillin-sensitive Staphylococcus aureus(MSSA) and Klebsiella pneumoniae. The data suggest that the sulfenimine moiety may be beneficial to the activity and selectivity of inhibitors.

A highly enantioselective domino reaction of α,β-unsaturated aldehydes and 4-acetyl-5-oxohexanal catalyzed by a chiral secondary amine catalyst has been developed, providing an efficient synthetic approach for the synthesis of densely functionalized chiral cyclohexene derivatives with high yields (up to 96%) and enantioselectivities (up to 97% ee) under mild conditions.

A series of pyrrolopyrazinone-chalcone hybrids(12a–12q) was designed, synthesized and screened for their antitumor activity against SKOV-3, A549 and HeLa cell lines in vitro. Compared with the pyrrolopyrazinone( 10a) and 5-fluorouracil(5-FU), nearly all the tested compounds showed significantly-improved antitumor activities. The most promising compounds 12e and 12k(IC50=0.25 and 0.88 μmol/L) respectively show activities of 123 and 35 times that of compound 10a(IC50=30.74 μmol/L) against HeLa cell line. The result reveals that the presence of chalcone moiety is beneficial to their activity and selectivity.

A series of pyrrolo[1,2-a]pyrazinone compounds (5a–9f) were synthesized, and their cytotoxic activity against SKOV-3, A549, HeLa cells in vitro were evaluated by the MTT method. Some of the compounds showed potential antitumor activity against three tumor cell lines. Among them, compounds 9c and 9d showed the most potent cytotoxic activity. The preliminary mechanism of action was discussed.We synthesized a series of novel pyrrolo[1,2-a]pyrazinone compounds based on the pyrrolo[1,2-a]pyrazinone core of natural product Palau’amine using established synthetic methods to identify potential antitumor agents. Some of the compounds showed potent antitumor activity against SKOV-3, A549, HeLa tumor cell lines and the preliminary mechanism of action were discussed.