https://www.selleckchem.com/products/envonalkib.html The cryptolactones A1, A2, B1, and B2 isolated from a Cryptomyzus sp. aphid were synthesized via the Mukaiyama aldol reaction and olefin metathesis. Their antipodes and derivatives were also synthesized by the same strategy to investigate structure-activity relationships. These compounds exhibited cytotoxic activity against human promyelocytic leukemia HL-60 cells with IC50 values of 2.1-42 µM.Tyrosinase plays important roles in many different disease related processes, and the development of its inhibitors is particularly important in biotechnology. In this study, thirty-nine 3-/4-alkoxyphenylethylidenethiosemicarbazides were synthesized as novel tyrosinase inhibitors based on structure-based molecular design. Our experimental results demonstrated that thirty-one of them possess remarkable tyrosinase inhibitory activities with IC50 value below 1 µM, and 5a, 6e, 6g and 6t did not display any toxicity to 293T cell line at the concentration of 1000 µmol/L. According to the inhibitory activities, several compounds were selected for detail investigation on the structure-activity relationships (SARs), mechanisms of enzyme inhibition, inhibitory kinetics and cytotoxicity. In particular, the interaction between the selected inhibitors and the active center of tyrosinase was considered and discussed in detail based on their structural characteristics. Taken together, the results presented here demonstrated that the newly designed compounds are promising candidates for the treatment of tyrosinase-related disorders and further development of them may have significant contribution in biomedical science.Poly(D,L-lactide-co-glycolic) acid (PLGA) is a synthetic copolymer that has been used to design micro/nanoparticles as a carrier for macromolecules, such as protein and nucleic acids, that can be internalized by the endocytosis pathway. However, it is difficult to control the intracellular delivery to target organelles. Here w