Cheng-Shi Jiang

Disulfide- and Multisulfide-Containing Metabolites from Marine Organisms

Disulfideand Multisulfide-Containing Metabolites from Marine Organisms Cheng-Shi Jiang, Werner E. G. M€uller, Heinz C. Schr€oder, and Yue-Wei Guo* State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang High-Tech Park, Shanghai 201203, People’s Republic of China Institute for Physiological Chemistry, Medical Center of the Johannes Gutenberg-University, Duesbergweg 6, D-55128 Mainz, Germany

Synthesis and biological evaluation of novel marine-derived indole-based 1,2,4-oxadiazoles derivatives as multifunctional neuroprotective agents

Phidianidines (1), isolated from the marine opisthobranch mollusk Phidiana militaris, present the first example of natural products possessing an 1,2,4-oxadiazole ring system and show various bioactivities. However, the structure-activity relationship study related to 1 has not been reported yet. As our ongoing effect toward marine-derived potential neuroprotective agents, a series of phidianidine-based derivatives have been synthesized and evaluated for neuroprotective effects against amyloid-β25-35 (Aβ25-35)-, hydrogenperoxide (H2O2)-, and oxygen-glucose deprivation (OGD)-induced neurotoxicity in SH-SY5Y cells. The bioassay results indicated that some of analogs, especially 2q and 2r, exhibited good in vitro neuroprotective effects in the above three screening models. The preliminary SAR study indicated that substituent groups introduced to the benzene ring play a crucial role in their bioactivity. In particular, the linear alkoxy group at 4-position favors the neuroprotective activity, while a bulky group could lead the activity decrease or loss. These findings could provide an alternative strategy for the development of novel indole-based 1,2,4-oxadiazole derivatives for the treatment of Alzheimers disease.

Recent progress regarding the bioactivities, biosynthesis and synthesis of naturally occurring resorcinolic macrolides.

Macrolides, which comprise a family of lactones with different ring sizes, belong to the polyketide class of natural products. Resorcinolic macrolides, an important subgroup, possess interesting structures and exhibit a wide variety of bioactivities, such as anti-tumor, anti-bacteria, and anti-malaria activities, etc. This review summarizes progress in isolation, bioactivity studies, biosynthesis, and representative chemical syntheses of this group of macrolides in recent decades, encompassing 63 naturally occurring macrolides published in 120 articles.

Synthesis and antitumor evaluation of methyl spongoate analogs

A series of novel methyl spongoate (1) analogs has been synthesized and evaluated for their in vitro cytotoxic properties. It was found that the nature of the C-20 side chain had significant effects on their bioactivities and some analogs showed higher cytotoxicity than 1 against A549, HCT-116, HepG2, SW-1990, MCF-7 and NCI-H460 tumor cell lines. The pharmacological results confirmed that the α,β-unsaturated carbonyl moiety, a Michael acceptor in ring A, plays a pivotal role in the cytotoxic effect of these derivatives. The compiled pharmacological data may be useful for the design of novel analogous anticancer drugs.

Synthesis, modification, and evaluation of (R)-de-O-methyllasiodiplodin and analogs as nonsteroidal antagonists of mineralocorticoid receptor.

Macrolide (R)-de-O-methyllasiodiplodin (1), discovered to be a potent nonsteroidal antagonist of the mineralocorticoid receptor (MR), was synthesized via an efficient method and evaluated for MR antagonistic activity together with its analogs. Among all the tested compounds, compounds 18a, 18b and 18c, exhibited more potent antagonistic activity against MR with IC(50) values ranging from 0.58 to 1.11 μM. Generally, it was obviously demonstrated that acetylation at phenolic hydroxyl groups and the ring size in analogs of 1 were very important for MR antagonist activity.

Synthesis and biological evaluation of 21-arylidenepregnenolone derivatives as neuroprotective agents.

A series of 21-arylidenepregnenolone derivatives and their corresponding epoxides were synthesized. The neuroprotective effects of these steroidal compounds against amyloid-β(25-35) (Aβ(25-35))- and hydrogen peroxide (H(2)O(2))-induced neurotoxicity in PC12 cells, and oxygen-glucose deprivation (OGD)-induced neurotoxicity in SH-SY5Y cells were evaluated. The bioassay results indicated that several 3β-pregn-21-benzylidene-20-one derivatives displayed potent in vitro neuroprotective effects in different screening models, for example, compounds 2b, 3a, 3b, and 3s showing significant activities against Aβ(25-35)-induced neurotoxicity in PC12 cells, 2b showing significant activities against H(2)O(2)-induced neurotoxicity in PC12 cells, and 2g, 3b, and 3e showing potent protection against OGD insult. The results suggested that introduction of an arylidene group into steroidal nucleus played an important role in neuroprotective activity, while the formation of epoxy group at C-5,6 could be also important for the neuroprotective activity in some degree. The pharmacological data reported here are helpful for the design of novel steroidal neuroprotective candidates.

Design, synthesis and in vitro activity of phidianidine B derivatives as novel PTP1B inhibitors with specific selectivity.

A series of phidianidine B derivatives were synthesized by introducing various heterocyclic rings. Their inhibitory effects on PTP1B and other PTPs (TCPTP, SHP1, SHP2 and LAR) were evaluated. A majority of them displayed significant inhibitory potency and specific selectivity over PTP1B. The SAR and molecular docking analysis were also described.

An updated overview on the development of new photosensitizers for anticancer photodynamic therapy

Photodynamic therapy (PDT), based on the photoactivation of photosensitizers (PSs), has become a well-studied therapy for cancer. Photofrin®, belonging to the first generation of PS, is still widely used for the treatment of different kinds of cancers; however, it has several drawbacks that significantly limit its general clinical use. Consequently, there has been extensive research on the design of PS molecules with optimized pharmaceutical properties, with aiming of overcoming the disadvantages of traditional PS, such as poor chemical purity, long half-life, excessive accumulation into the skin, and low attenuation coefficients. The rational design of novel PS with desirable properties has attracted considerable research in the pharmaceutical field. This review presents an overview on the classical photosensitizers and the most significant recent advances in the development of PS with regard to their potential application in oncology.

Synthesis and evaluation of novel 1,2,3-triazole-based acetylcholinesterase inhibitors with neuroprotective activity.

A series of new 1,2,3-triazole derivatives were synthesized and evaluated for anticholinesterase and neuroprotective activities. Some synthetic derivatives, especially compound 32, exhibited improved acetylcholinesterase (AChE) inhibitory activity by comparison with the hit 1, high selectivity toward AChE over butyrylcholinesterase (BuChE), and suitable in vitro neuroprotective effect against amyloid-β25-35 (Aβ25-35)-induced neurotoxicity in SH-SY5Y cells. Furthermore, these molecules have desired physicochemical properties in the range of CNS drugs and showed no cytotoxicity against two normal cells, including human keratinocytes HaCaT and murine fibroblasts NIH-3T3. The preliminary bioassay results and docking study indicated that compound 32 might be a promising lead compound with dual action for the treatment of Alzheimers disease.

The first synthesis of natural disulfide bruguiesulfurol and biological evaluation of its derivatives as a novel scaffold for PTP1B inhibitors

Bruguiesulfurol (1), a cyclic 4-hydroxy-dithiosulfonate isolated from mangrove plant Bruguiera gymnorrhiza, was concisely synthesized for the first time in four steps, and a series of its synthetic derivatives were evaluated for in vitro inhibitory effects on PTP1B and related PTPs. Some derivatives were found to have improved pharmacological profile compared with hit 1. Among them, 5a showed the potent selectivity towards PTP1B over other PTPs, including TCPTP, and 7j exhibited the strongest PTP1B inhibitory activity with an IC50 value of 4.54 μM.