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Ascomycin(FK 520)

Catalog No.
Macrolide immunosuppressant,FK-520 analog
Grouped product items
SizePriceStock Qty
10mM (in 1mL DMSO)
In stock
In stock
In stock

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Ascomycin (FK 520, FR900520) is a novel neutral macrolide immunosuppressant, isolated from the cultured broth of Streptomyces hygroscopicus subsp. yakushimaensis No. 7238.

In vitro: Ascomycin (FK 520, FR900520) suppressed lymphocyte reaction in a dose dependent fashion. Ascomycin was non-toxic at concentrations less than 3,200 nM, at which the percent inhibition was 18.9%. Ascomycin showed antifungal activity against Aspergillus fumigatus IFO 5840. Ascomycin had no inhibitory effect on bacteria or yeast at 100 μg/ml [1].

In vivo: Ascomycin was dose-dependently effective and clearly prolonged skin allograft survival at 3.2 mg/kg or more, though all skin allografts were rejected within 7 days in rats treated intramuscularly with olive oil. Ascomycin, dissolved in olive oil, showed no adverse effect when administered intraperitoneally to ddY mice (male, 8 weeks old) at 100 mg/kg [1].

Clinical trial: Ascomycin macrolactam derivative, Pimecrolimus, had been tested in both adults and pediatric patients with Atopic Dermatitis in two seperate clinical trials.

[1] Hatanaka H, Kino T, Miyata S, Inamura N, Kuroda A, Goto T, Tanaka H, Okuhara M.  FR-900520 and FR-900523, novel immunosuppressants isolated from a Streptomyces. II. Fermentation, isolation and physico-chemical and biological characteristics. J Antibiot (Tokyo). 1988;41(11):1592-601.

Chemical Properties

Physical AppearanceA solid
StorageStore at -20°C
Cas No.104987-12-4
SynonymsImmunomycin;FK 520;FR 900520;FR-900520;FR900520;FK-520;FK520
Solubility≥38.9 mg/mL in DMSO, ≥98.6 mg/mL in EtOH,insoluble in H2O
SDFDownload SDF
Shipping ConditionEvaluation sample solution : ship with blue ice.All other available size: ship with RT , or blue ice upon request
General tipsFor obtaining a higher solubility , please warm the tube at 37 ℃ and shake it in the ultrasonic bath for a while.Stock solution can be stored below -20℃ for several months.

Biological Activity

Description Ascomycin is a macrolide immunosuppressant antibiotic.
Targets peptidyl-prolyl cis-trans isomerase PfFKBP35        
IC50   0.52 μM        

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