C-Nitrosothioformamide: A Donor Template for Dual Release of HNO and H2 S.

C-Nitrosothioformamide was demonstrated to be a donor template for dual release of HNO and COS triggered by a retro-Diels-Alder reaction. COS is an H2 S precursor in the presence of carbonic anhydrase. This process produces HNO and H2 S in a slow but steady manner. As such, the direct reaction between HNO and H2 S under this situation appears to be minor. This may provide a useful tool for studying the synergistic effects of HNO and H2 S.

O→S Relay Deprotection: A General Approach to Controllable Donors of Reactive Sulfur Species.

Reactive sulfur species (RSS) are biologically important molecules. Among them, H2 S, hydrogen polysulfides (H2 Sn, n>1), persulfides (RSSH), and HSNO are believed to play regulatory roles in sulfur-related redox biology. However, these molecules are unstable and difficult to handle. Having access to their reliable and controllable precursors (or donors) is the prerequisite for the study of these sulfur species. Reported in this work is the preparation and evaluation of a series of O-silyl-mercaptan-based sulfur-containing molecules which undergo pH- or F- -mediated desilylation to release the corresponding H2 S, H2 Sn , RSSH, and HSNO in a controlled fashion. This O→S relay deprotection serves as a general strategy for the design of pH- or F- -triggered RSS donors. Moreover, we have demonstrated that the O-silyl groups in the donors could be changed into other protecting groups like esters. This work should allow the development of RSS donors with other activation mechanisms (such as esterase-activated donors).

Inorganic hydrogen polysulfides: chemistry, chemical biology and detection.

Recent studies suggest that inorganic hydrogen polysulfides (H2 Sn , n ≥ 2) play important regulatory roles in redox biology. Modulation of their cellular levels could have potential therapeutic value. This review article focuses on our current understanding of the biosynthesis, biofunctions, fundamental physical/chemical properties, detection methods and delivery techniques of H2 Sn . LINKED ARTICLES: This article is part of a themed section on Chemical Biology of Reactive Sulfur Species. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.4/issuetoc.

Synthesis of Unsymmetric Trisulfides from 9-Fluorenylmethyl Disulfides.

A convenient method for the preparation of unsymmetrical trisulfides using 9-fluorenylmethyl (Fm) disulfide as the precursors is reported. This method gives the desired trisulfides in good yields under mild conditions.