Rhizoxin

Rhizoxin is an antimitotic agent with anti-tumor activity.^[1][2] It is isolated from the fungus Rhizopus microsporus which causes rice seedling blight.

Rhizoxin

Identifiers
CAS Number	90996-54-6 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:72590
ChEMBL	ChEMBL379989 N
ChemSpider	10405026
PubChem CID	11969567
UNII	C1V1Y784E4 Y
CompTox Dashboard (EPA)	DTXSID20897515
InChI InChI=1S/C35H47NO9/c1-19(13-25-18-41-23(5)36-25)9-8-10-21(3)32(40-7)22(4)27-17-29(37)35(6)30(45-35)12-11-20(2)26-14-24(16-31(38)42-26)15-28-33(43-28)34(39)44-27/h8-13,18,20,22,24,26-30,32-33,37H,14-17H2,1-7H3/b9-8+,12-11+,19-13+,21-10+/t20-,22+,24+,26-,27+,28+,29+,30-,32+,33-,35-/m1/s1 Key: OWPCHSCAPHNHAV-QIPOKPRISA-N
SMILES O=C1C[C@@](C[C@H]3[C@H]2O3)([H])C[C@@]([C@H](C)/C=C/[C@@H](O4)[C@]4(C)[C@@H](O)C[C@]([C@H](C)[C@@H](OC)/C(C)=C/C=C/C(C)=C/C5=COC(C)=N5)([H])OC2=O)([H])O1
Properties
Chemical formula	C35H47NO9
Molar mass	625.749 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Biosynthesis

Rhizoxin is biosynthesised by Paraburkholderia rhizoxinica, a bacterial endosymbiont of the fungus Rhizopus microsporus.^[3] It is one of a large group of rhizoxin-like compounds produced by the bacteria.^[4] The bacterial endosymbiont can be grown independently in culture. This may allow easy harvesting of rhizoxin and the related compounds avoiding total chemical synthesis, although total chemical synthesis is possible.^[5]

Cytotoxic function

Rhizoxin binds beta tubulin in eukaryotic cells disrupting microtubule formation. This, in turn, prevents formation of the mitotic spindle inhibiting cell division. Additionally rhizoxin can depolymerise assembled microtubules.^[6] The function of rhizoxin is similar to Vinca alkaloids.

Rhizoxin has undergone clinical trials as an anti-cancer drug^[7] although it did not reach later stages of clinical trials due to low activity in vivo. Related compounds to rhizoxin have improved biological activity (E.G Mertansine) .^[4]

Structure

Rhizoxin is a 16-membered lactone ring connected to an oxazole ring by a long unsaturated chain.^[8]