Wikipedia:  

lactulose

4-O-beta-D-Galactopyranosyl-D-fructofuranose; 4-O-beta-D-Galactopyranosyl-D-fructose; Lactulose
Molecular Formula
C12 H22 O11
Natural Isotopic Abundance Mass
342.29648
Mono-Isotopic Molecular Masses
C12N14:   342.1162115493
C13N14:   354.1564696029
C12N15:   342.1162115493
C13N15:   354.1564696029
lactulose image
lactulose
InCHi String:
InChI=1S/C12H22O11/c13-1-4-6(16)7(17)8(18)11(21-4)22-9-5(2-14)23-12(20,3-15)10(9)19/h4-11,13-20H,1-3H2/t4-,5-,6+,7+,8-,9-,10+,11+,12+/m1/s1

canonical SMILES:
C(C1C(C(C(C(O1)OC2C(OC(C2O)(CO)O)CO)O)O)O)O
isomeric SMILES:
C([C@@H]1[C@@H]([C@@H]([C@H]([C@@H](O1)O[C@@H]2[C@H](O[C@]([C@H]2O)(CO)O)CO)O)O)O)O


PUBCHEM iupac NAME: PUBCHEM iupac SYSTEMATIC NAME
(2S,3R,4S,5R,6R)-2-[(2R,3S,4S,5S)-4,5-dihydroxy-2,5-bis(hydroxymethyl)oxolan-3-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol

PUBCHEM iupac TRADITIONAL NAME
(2S,3R,4S,5R,6R)-2-[(2R,3S,4S,5S)-4,5-dihydroxy-2,5-dimethylol-tetrahydrofuran-3-yl]oxy-6-methylol-tetrahydropyran-3,4,5-triol

PUBCHEM iupac OPENEYE NAME
(2S,3R,4S,5R,6R)-2-[(2R,3S,4S,5S)-4,5-dihydroxy-2,5-bis(hydroxymethyl)tetrahydrofuran-3-yl]oxy-6-(hydroxymethyl)tetrahydropyran-3,4,5-triol

PUBCHEM iupac CAS NAME
(2S,3R,4S,5R,6R)-2-[[(2R,3S,4S,5S)-4,5-dihydroxy-2,5-bis(hydroxymethyl)-3-tetrahydrofuranyl]oxy]-6-(hydroxymethyl)tetrahydropyran-3,4,5-triol



PubChem Substance (SID):   111677791   57380967   24896485
PubChem Compound (CID):   16217605
KEGG: Compound ID   n/a
CAS Registry IDs:   n/a
PDB Chemical Component   n/a
Miscellaneous Databases and IDs:   Sigma-Aldrich L7877_SIGMA   ChemSpider 17345122   NovoSeek 16217605   MMCD cq_04148   MDL MFCD00151469

Reference data were obtained primarily from the PubChem database.

Three dimensional molecular rendering uses Jmol.