Molecular Structure of Basic Green 4 (CAS NO.2437-29-8):

IUPAC Name: [4-[(4-dimethylaminophenyl)-phenylmethylidene]cyclohexa-2,5-dien-1-ylidene]-dimethylazanium; 2-hydroxy-2-oxoacetate; oxalic acid
Molecular formula: C₅₂H₅₄N₄O₁₂
Molecular Weight: 927
CAS: 2437-29-8
Merck: 14,5699
BRN: 3644550
EINECS: 219-441-7
Melting point: 164°C (dec.)
Storage temp: Store at RT
Water Solubility: 60 g/L (20 °C)
Appearance: dark green crystals with a metallic luster
Stability: Stable. Substances to be avoided include strong oxidizing agents
Product Categories: Ion Association; Analytical Chemistry

Poison by ingestion. A severe eye irritant. Mutation data reported. When heated to decomposition it emits toxic fumes of NO_x. See also Oxalates.
The Hazard Codes of  Basic Green 4 (CAS NO.2437-29-8): Xn,N
HazardClass: 6.1(b)
Risk Statements information:
21:  Harmful in contact with skin 
22:  Harmful if swallowed 
25:  Toxic if swallowed 
41:  Risk of serious damage to eyes 
63:  Possible risk of harm to the unborn child 
20/21/22:  Harmful by inhalation, in contact with skin and if swallowed 
36/37/38:  Irritating to eyes, respiratory system and skin 
50/53:  Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment 
Safety Statements information:
2:  Keep out of the reach of children 
22:  Do not breathe dust 
26:  In case of contact with eyes, rinse immediately with plenty of water and seek medical advice 
36:  Wear suitable protective clothing 
39:  Wear eye/face protection 
45:  In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) 
46:  If swallowed, seek medical advice immediately and show this container or label 
60:  This material and/or its container must be disposed of as hazardous waste 
61:  Avoid release to the environment. Refer to special instructions safety data sheet 
36/37:  Wear suitable protective clothing and gloves 
36/37/39:  Wear suitable protective clothing, gloves and eye/face protection 
RIDADR: UN 2811 6.1/PG 3
WGK Germany: 3
RTECS: BQ1190000
PackingGroup: III
HS Code: 32041300

  Basic Green 4 , with CAS number of 2437-29-8, can be called Ammonium, (4-(p-(dimethylamino)-alpha-phenylbenzylidene)-2,5-cyclohexadien-1-ylidene)-dimethyl-, oxalate (2:1), oxalate (1:1) ; Bis((4-(4-(dimethylamino)benzhydrylidene)cyclohexa-2,5-dien-1-ylidene)dimethylammonium) oxalate, dioxalate ; Methanaminium, N-(4-((4-(dimethylamino)phenyl)phenylmethylene)-2,5-cyclohexadien-1-ylidene)-N-methyl-, ethanedioate (2:2:1) ; Methanaminium, N-(4-((4-(dimethylamino)phenyl)phenylmethylene)-2,5-cyclohexadien-1-ylidene)-N-methyl-, ethanedioate, ethanedioate (2:2:1) . It is a  dark green crystals with a metallic luster.