Dirithromycin is a macrolide glycopeptide antibiotic.^[1]

Dirithromycin

Clinical data
Trade names	Dynabac
AHFS/Drugs.com	Micromedex Detailed Consumer Information
MedlinePlus	a604026
License data	US FDA: Clarithromycin
Pregnancy category	B
Routes of administration	Oral
ATC code	J01FA13 (WHO)
Pharmacokinetic data
Bioavailability	10%
Protein binding	15 to 30%
Metabolism	Hyrolized to erythromycyclamine in 1.5 hours
Identifiers
IUPAC name (2R,3R,6R,7S,8S,9R,10R,12R,13S,15R,17S)-9-{[(2S,3R,4S,6R)-4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy}-3-ethyl-2,10-dihydroxy-7-{[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy}-15-[(2-methoxyethoxy)methyl]-2,6,8,10,12,17-hexamethyl-4,16-dioxa-14-azabicyclo[11.3.1]heptadecan-5-one
CAS Number	62013-04-1 Y
PubChem CID	6917067
DrugBank	DB00954 Y
ChemSpider	5292341 Y
UNII	1801D76STL
KEGG	D03865 Y
ChEBI	CHEBI:474014 N
ChEMBL	ChEMBL3039471 N
CompTox Dashboard (EPA)	DTXSID7048956
ECHA InfoCard	100.152.704
Chemical and physical data
Formula	C42H78N2O14
Molar mass	835.086 g·mol−1
3D model (JSmol)	Interactive image
Melting point	186 to 189 °C (367 to 372 °F) (dec.)
SMILES O=C4O[C@@H]([C@](O)(C)[C@H]1O[C@@H](N[C@H]([C@@H]1C)[C@H](C)C[C@](O)(C)[C@H](O[C@@H]2O[C@H](C)C[C@H](N(C)C)[C@H]2O)[C@H]([C@H](O[C@@H]3O[C@@H](C)[C@H](O)[C@@](OC)(C)C3)[C@H]4C)C)COCCOC)CC
InChI InChI=1S/C42H78N2O14/c1-15-29-42(10,49)37-24(4)32(43-30(56-37)21-52-17-16-50-13)22(2)19-40(8,48)36(58-39-33(45)28(44(11)12)18-23(3)53-39)25(5)34(26(6)38(47)55-29)57-31-20-41(9,51-14)35(46)27(7)54-31/h22-37,39,43,45-46,48-49H,15-21H2,1-14H3/t22-,23-,24+,25+,26-,27+,28+,29-,30-,31+,32+,33-,34+,35+,36-,37+,39+,40-,41-,42-/m1/s1 Y Key:WLOHNSSYAXHWNR-NXPDYKKBSA-N Y
NY (what is this?)  (verify)

Dirithromycin (Dynabac) is a more lipid-soluble prodrug derivative of 9S-erythromycyclamine prepared by condensation of the latter with 2-(2-methoxyethoxy)acetaldehyde. The 9N, 11O-oxazine ring thus formed is a hemi-aminal that is unstable under both acidic and alkaline aqueous conditions and undergoes spontaneous hydrolysis to form erythromycyclamine. Erythromycyclamine is a semisynthetic derivative of erythromycin in which the 9-ketogroup of the erythronolide ring has been converted to an amino group. Erythromycyclamine retains the antibacterial properties of erythromycin oral administration. The prodrug, dirithromycin, is provided as enteric coated tablets to protect it from acid catalyzed hydrolysis in the stomach. Orally administered dirithromycin is absorbed rapidly into the plasma, largely from the small intestine. Spontaneous hydrolysis to erythromycyclamine occurs in the plasma. Oral bioavailability is estimated to be about 10%, but food does not affect absorption of the prodrug.