S-Nitroso-N-acetylpenicillamine

From Wikipedia, the free encyclopedia

S-Nitroso-N-acetylpenicillamine
IUPAC name S-Nitroso-N-acetylpenicillamine
Other names N-Acetyl-3-(nitrosothio)-DL-valine
S-Nitroso-N-acetylpenicillamine
Identifiers
Abbreviations SNAP
CAS number [67776-06-1]
PubChem 5231
Properties
Molecular formula C7H12N2O4S
Molar mass 220.25 g/mol
Hazards
R-phrases 36/37/38
S-phrases 26-36
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

S-Nitroso-N-acetylpenicillamine is the chemical compound with the formula ONSC(CH3)2CH(NHAc)CO2H (Ac = acetyl). The molecule is an important donor of the NO+ in biochemistry. It has received much attention because nitric oxide and some organic nitroso derivatives serve as signaling molecules in living systems, especially related to vasodilation. SNAP is used as a model for the general class of S-nitrosothiols.[1] S-Nitrosoglutathione is a related agent.

[edit] Organic chemistry background

SNAP is derived from the amino acid penicillamine. The prefix "S" indicates that the NO group is attached to sulfur.

Nitrosothiols contain the RS-N=O functional group (R = alkyl, aryl). The S-N-O angle deviates strongly from 180° because the nitrogen atom bears of lone pair of electrons.

Thionitroso compounds arise from condensation from nitrous acid and a thiol:[2]

RSH + HONO → RSNO + H2O

Many other methods exist for their synthesis. Once formed, these deeply coloured compounds are often thermally unstable with respect to formation of the disulfide and nitric oxide.

SNAP releases NO+ upon treatment with acids:

RSNO + H+ → RSH + NO+

Thionitroso compounds transfer NO to other thiols:

RSNO + R'SH → RSH + R'SNO

[edit] References

  1. ^ Zhang Y.; Hogg, N. “S-Nitrosothiols: cellular formation and transport” Free Radical Biology and Medicine 2005, volume 38, pp. 831-838. doi:10.1016/j.freeradbiomed.2004.12.016
  2. ^ Wang, P. G.; Xian, M.; Tang, X.; Wu, X.; Wen, Z.; Cai, T.; Janczuk, A. J., "Nitric Oxide Donors: Chemical Activities and Biological Applications", Chemical Reviews, 2002, 102, 1091 - 1134.doi:10.1021/cr000040l