Salinosporamide A

Salinosporamide A

Names
IUPAC name (4R,5S)-4-(2-chloroethyl)-1-((1S)-cyclohex-2-enyl(hydroxy)methyl)-5-methyl-6-oxa-2-azabicyclo[3.2.0]heptane-3,7-dione
Other names Marizomib; NPI-0052
Identifiers
CAS Number	437742-34-2 N
3D model (JSmol)	Interactive image Interactive image
ChEBI	CHEBI:48045 N
ChemSpider	9522473 N
KEGG	D09640
PubChem CID	11347535
InChI InChI=1S/C15H20ClNO4/c1-14-10(7-8-16)12(19)17-15(14,13(20)21-14)11(18)9-5-3-2-4-6-9/h3,5,9-11,18H,2,4,6-8H2,1H3,(H,17,19)/t9-,10+,11+,14+,15+/m1/s1 N Key: NGWSFRIPKNWYAO-SHTIJGAHSA-N N InChI=1/C15H20ClNO4/c1-14-10(7-8-16)12(19)17-15(14,13(20)21-14)11(18)9-5-3-2-4-6-9/h3,5,9-11,18H,2,4,6-8H2,1H3,(H,17,19)/t9-,10+,11+,14+,15+/m1/s1 Key: NGWSFRIPKNWYAO-SHTIJGAHBB
SMILES O=C1O[C@@]3(C)[C@H](C(=O)N[C@@]13[C@@H](O)[C@@H]2/C=C\CCC2)CCCl C[C@]13OC(=O)C3(NC(=O)[C@@H]1CCCl)[C@@H](O)C2/C=C\CCC2
Properties
Chemical formula	C15H20ClNO4
Molar mass	313.781 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Salinosporamide A (Marizomib) is a potent proteasome inhibitor being studied as a potential anticancer agent. It entered phase I human clinical trials for the treatment of multiple myeloma, only three years after its discovery in 2003. This marine natural product is produced by the obligate marine bacteria Salinispora tropica and Salinispora arenicola, which are found in ocean sediment. Salinosporamide A belongs to a family of compounds, known collectively as salinosporamides, which possess a densely functionalized γ-lactam-β-lactone bicyclic core.

Salinosporamide A was discovered by William Fenical and Paul Jensen from Scripps Institution of Oceanography in La Jolla, CA. In preliminary screening, a high percentage of the organic extracts of cultured Salinospora strains possessed antibiotic and anticancer activities, which suggests that these bacteria are an excellent resource for drug discovery. Salinospora strain CNB-392 was isolated from a heat-treated marine sediment sample and cytotoxicity-guided fractionation of the crude extract led to the isolation of salinosporamide A. Although salinosporamide A shares an identical bicyclic ring structure with omuralide, it is uniquely functionalized. Salinosporamide A displayed potent in vitro cytotoxicity against HCT-116 human colon carcinoma with an IC50 value of 11 ng mL-1. This compound also displayed potent and highly selective activity in the NCI's 60-cell-line panel with a mean GI50 value (the concentration required to achieve 50% growth inhibition) of less than 10 nM and a greater than 4 log LC50 differential between resistant and susceptible cell lines. The greatest potency was observed against NCI-H226 non-small cell lung cancer, SF-539 CNS cancer, SK-MEL-28 melanoma, and MDA-MB-435 breast cancer (all with LC50 values less than 10 nM). Salinosporamide A was tested for its effects on proteasome function because of its structural relationship to omuralide. When tested against purified 20S proteasome, salinosporamide A inhibited proteasomal chymotrypsin-like proteolytic activity with an IC50 value of 1.3 nM. This compound is approximately 35 times more potent than omuralide which was tested as a positive control in the same assay. Thus, the unique functionalization of the core bicyclic ring structure of salinosporamide A appears to have resulted in a molecule that is a significantly more potent proteasome inhibitor than omuralide.