Lactose

Lactose

Molecular structure via molpic based on CDK

Physical properties []
Molecular mass	342.30 g/mol ^[1]
Density	1.525 g/cm³ ^[1]
Appearance	White, hard, crystalline mass of white powder ^[1]
Odor	Odorless ^[1]
Taste	Sweet ^[1]
Melting point	433 ° ^[1]
Solubility	50 to 100 mg/mL at 68 °F (NTP, 1992) ^[1]
Predicted LogP	-4.7 ^[1]

Structural Identifiers []
Molecular formula	C₁₂H₂₂O₁₁ ^[1]
IUPAC name	(2R,3R,4S,5R,6S)-2-(hydroxymethyl)-6-[(2R,3S,4R,5R)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxane-3,4,5-triol ^[1]
SMILES	C([C@@H]1[C@@H]([C@@H]([C@H]([C@@H](O1)O[C@@H]2[C@H](OC([C@@H]([C@H]2O)O)O)CO)O)O)O)O ^[1]
InChI	InChI=1S/C12H22O11/c13-1-3-5(15)6(16)9(19)12(22-3)23-10-4(2-14)21-11(20)8(18)7(10)17/h3-20H,1-2H2/t3-,4-,5+,6+,7-,8-,9-,10-,11?,12+/m1/s1 ^[1]
InChIKey	GUBGYTABKSRVRQ-QKKXKWKRSA-N ^[1]

Lactose (also known as Lactose, lactose, Milk sugar, Chebi:17716, β-D-Gal-(1->4)-D-Glc, β-D-Galp-(1->4)-D-Glcp, 1-β-D-Galactopyranosyl-4-D-glucopyranose, β-D-galactopyranosyl-(1->4)-D-glucopyranose, Lactin or Anhydrous lactose)

Chemistry

Stereochemistry []

Lactose is a racemic mixture of the enantiomers.

Stereoisomerism
(1R,2R)-3S)-4R)-5S)-8S)-9R)-11R)-12R)-13R)-Lactose (1R,2R)-3S)-4R)-5S)-8S)-9R)-11S)-12R)-13R)-Lactose
Stereoisomer enumberation with rdkit

Pharmacology

ATC Classification

Metabolism

Subjective effects []

0xea / Lactose []
Routes: Oral Active Effects: acutely causes acne

0xea / Lactose []

Routes:

Oral

Active Effects:

acutely causes acne

External links []

References []

National Center for Biotechnology Information. PubChem Compound Summary for CID 440995, Lactose. Accessed April 11, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/440995

AnodyneWiki