Melting point :4-5 °C (lit.)
Boiling point :86-87 °C/12 mmHg (lit.)
Density :1.185 g/mL at 25 °C (lit.)
FEMA :4138 | 4-HYDROXY-2-BUTENOIC ACID GAMMA-LACTONE
refractive index :n20/D 1.469(lit.)
Flash point :214 °F
storage temp. :2-8°C
solubility :Chloroform, Ethyl Acetate (Slightly)
form :Liquid
color :Clear colorless to pale yellow or amber
Odor :buttery
Odor Type :buttery
Water Solubility :Immiscible with water.
JECFA Number :2000
BRN :383585
Henry's Law Constant :3.5×10^-1 mol/(m³Pa) at 25℃, Wang et al. (2017)
Stability :Moisture Sensitive
InChI :1S/C4H4O2/c5-4-2-1-3-6-4/h1-2H,3H2
InChIKey :VIHAEDVKXSOUAT-UHFFFAOYSA-N
SMILES :O=C1OCC=C1
LogP :-0.600
CAS DataBase Reference :497-23-4(CAS DataBase Reference)
NIST Chemistry Reference :2(5H)-Furanone(497-23-4)
EPA Substance Registry System :2(5H)-Furanone (497-23-4)

Symbol(GHS):
Signal word:	Warning
Hazard statements:	Code Hazard statements Hazard class Category Signal word Pictogram P-Codes H315 Causes skin irritation Skin corrosion/irritation Category 2 Warning P264, P280, P302+P352, P321,P332+P313, P362 H319 Causes serious eye irritation Serious eye damage/eye irritation Category 2A Warning P264, P280, P305+P351+P338,P337+P313P
Precautionary statements:	P264 Wash hands thoroughly after handling. P264 Wash skin thouroughly after handling. P280 Wear protective gloves/protective clothing/eye protection/face protection. P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing. P321 Specific treatment (see … on this label). P332+P313 IF SKIN irritation occurs: Get medical advice/attention. P337+P313 IF eye irritation persists: Get medical advice/attention.