Green S

Green S
Names
	IUPAC name Sodium 4-[(4-dimethylaminophenyl)-(4-dimethylazaniumylidene-1-cyclohexa-2,5-dienylidene)methyl]-3-hydroxynaphthalene-2,7-disulfonate
	Other names Food green S; FD&C green 4; acid green 50; lissamine green B; wool green S; C.I. 44090; E142;
Identifiers
CAS Number	3087-16-9 ;
3D model (JSmol)	Interactive image;
ChemSpider	82646 ;
ECHA InfoCard	100.019.463
E number	E142 (colours)
PubChem CID	91525;
UNII	9B7E8Y9D0X ;
CompTox Dashboard (EPA)	DTXSID4046577 ;
	InChI InChI=1S/C27H26N2O7S2.Na/c1-28(2)20-9-5-17(6-10-20)25(18-7-11-21(12-8-18)29(3)4)26-23-14-13-22(37(31,32)33)15-19(23)16-24(27(26)30)38(34,35)36;/h5-16H,1-4H3,(H2,31,32,33,34,35,36);/q;+1/p-1 Key: WDPIZEKLJKBSOZ-UHFFFAOYSA-M ; InChI=1/C27H26N2O7S2.Na/c1-28(2)20-9-5-17(6-10-20)25(18-7-11-21(12-8-18)29(3)4)26-23-14-13-22(37(31,32)33)15-19(23)16-24(27(26)30)38(34,35)36;/h5-16H,1-4H3,(H2,31,32,33,34,35,36);/q;+1/p-1 Key: WDPIZEKLJKBSOZ-REWHXWOFAE;
	SMILES [Na+].[O-]S(=O)(=O)c1ccc4c(c1)cc(c(O)c4/C(=C2\C=C/C(=[N+](/C)C)/C=C2)c3ccc(N(C)C)cc3)S([O-])(=O)=O;
Properties
Chemical formula	C27H25N2NaO7S2
Molar mass	576.62 g/mol
Melting point	210 °C (410 °F; 483 K) (decomposes)
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H315, H319, H335
Precautionary statements	P261, P305+P351+P338
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Green S is a green synthetic coal tar triarylmethane dye with the molecular formula C₂₇H₂₅N₂O₇S₂Na.

As a food dye, it has E number E142. It can be used in mint sauce, desserts, gravy granules, sweets, ice creams, and tinned peas. Green S is prohibited as a food additive in Canada, United States, Japan, and Norway.^[3] It is approved for use as a food additive in the EU^[4] and Australia and New Zealand.^[5]

Green S is a vital dye, meaning it can be used to stain living cells. It is used in ophthalmology, along with fluorescein and rose bengal, to diagnose various disorders of the eye's surface, dry eyes for example.

References

^ "Safety Data Sheet for Green S". Sigma-Aldrich.
^ Sigma-Aldrich Co., Green B. Retrieved on 2019-06-09.
^ "Green S". Ataman Chemicals. Retrieved 5 May 2024.
^ UK Food Standards Agency: "Current EU approved additives and their E Numbers". Retrieved 2011-10-27.
^ Australia New Zealand Food Standards Code"Standard 1.2.4 - Labelling of ingredients". 8 September 2011. Retrieved 2011-10-27.