1. Basic Identification Information

Parameter	English Specification/Value
IUPAC Name	(2Z,4E,6E,8E)-3,7-dimethyl-9-(2,6,6-trimethylcyclohex-1-en-1-yl)nona-2,4,6,8-tetraenoic acid (13-cis isomer)
Common Name(s)	Isotretinoin; 13-cis-Retinoic Acid; Accutane® (former brand); Roaccutane®; Claravis®
CAS Registry Number	4759-48-2
EC/EINECS Number	225-296-0
Molecular Formula	C₂₀H₂₈O₂
Molecular Weight	300.44 g/mol
Chemical Class	Retinoid (vitamin A derivative); anti-acne pharmaceutical; keratin-regulating agent
Related Compound	Tretinoin (all-trans-retinoic acid, CAS 302-79-4) (topical anti-acne/anti-aging agent with lower systemic toxicity but weaker efficacy for severe acne); Adapalene (CAS 106685-40-9) (synthetic retinoid with reduced irritation risk)

2. Physicochemical Properties

Property Category	Specific Parameter	Specification/Value
Structural Features	Functional Groups	Tetraene conjugated system (4 double bonds); carboxylic acid group (-COOH) at C1; trimethylcyclohexene ring at C9; 13-cis configuration (distinguishes from all-trans tretinoin and reduces binding affinity to some retinoid receptors)
Physical Appearance	State & Color	Yellow to orange crystalline powder; odorless; sensitive to light and air (oxidizes to inactive metabolites)
	Melting Point	174–175 °C (lit., decomposes above 200 °C)
	Boiling Point	Decomposes before boiling (releases volatile retinoid fragments above 250 °C)
	Density (25 °C)	1.02 g/cm³ (crystalline form)