F-4900 FK-506, >99%

Synonyms : [FR-900506]

Related Terms : [Fujimycin] [Prograf] [Tacrolimus]

  • Size
  • US $
  • £
  • ¥
  • 50 mg
  • 62
  • 51
  • 44
  • 6,700
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  • In stock
  • 100 mg
  • 107
  • 89
  • 77
  • 11,600
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  • In stock
  • 200 mg
  • 158
  • 131
  • 114
  • 17,200
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  • In stock
  • 500 mg
  • 239
  • 199
  • 172
  • 26,000
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  • 1 g
  • 347
  • 289
  • 250
  • 37,800
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  • 2 g
  • 585
  • 488
  • 422
  • 63,700
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  • In stock
  • 5 g
  • 1,065
  • 889
  • 769
  • 115,900
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  • In stock

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  • M.W. 804.02
  • C44H69NO12
  • [104987-11-3]
  • M.I. 13: 9117
  • M.I. 14: 9025

Storage: Store at or below -20 ºC. Solubility: Soluble in DMSO at 100 mg/mL; soluble in ethanol at 100 mg/mL; very poorly soluble in water; maximum solubility in plain water is estimated to be about 10 µM; buffers, serum, or other additives may increase or decrease the aqueous solubility. Disposal: A.

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View the SDS for this product

  • More than 920 labs worldwide have purchased FK-506 from LC Labs (either directly from us or from our many distributors, many of whom resell under their own labels).
  • Ascomycin level is less than 0.9%.
  • FK-506 is a potent immunosuppressant and in vitro T cell proliferation blocker. It has been shown to disrupt calcineurin (also known as CaN or phosphatase 2B)-mediated signal transduction in T lymphocytes. The compound interacts with its FK506-binding protein-12 (FKBP12). The resulting complex, in turn, interferes with calcineurin substrate interaction. Dumont, F.J. "FK506, an immunosuppressant targeting calcineurin function." Curr. Med. Chem. 7: 731-748 (2000).
  • FK-506 inhibits FKBP activity resulting in an increase in the release of sarcoplasmic reticulum-derived calcium. FK-506 also appears to inhibit Na(+)-Ca2+ exchange. Unlike rapamycin, which also binds to FK506-binding protein-12, FKBP12 with or without bound FK506 has no effect on rat brain PKC activity in vitro. McCall, E., et al. "Effects of FK-506 on contraction and Ca2+ transients in rat cardiac myocytes." Circ. Res. 79: 1110-1121 (1996). Rokaw, M.D., et al. "Rapamycin inhibits protein kinase C activity and stimulates Na+ transport in A6 cells." J. Biol. Chem. 271: 32468-32473 (1996).
  • Water content of LC Labs' F-4900, FK506
    February 1, 2021: In the past, we did not attempt or purport to control the water content of our FK-506 product, and we have been using the CAS number assigned to the anhydrous form.

    However, we plan to offer both forms of FK-506 as separate products in the near future.

    The monohydrate will be offered under our current catalog number F-4900, and the anhydrous form will be F-4999.  (It is relatively simple to convert either form to the other.)  The two products will each use the appropriate CAS number.  

    Here are the water levels of our most recent lots, as determined by elemental analysis:
    ATH-123   0.9 eq
    ATH-122   0.9 eq
    ATH-121   1.0 eq
    ATH-120   1.0 eq
    ATH-119   none

  • Drying compounds to the point of complete absence of water is often a completely futile exercise, because many organic compounds rapidly rehydrate when opened to the air, even for short periods of time, in normal use.  The rate and avidity of such re-hydration is sometimes very impressive, indeed awesome in some cases, even for compounds that are not generally recognized as being hydroscopic.
  • Sold for laboratory or manufacturing purposes only; not for human, medical, veterinary, food, or household use.
  • Please see also our other standard immunosuppressant products:
    A-1040 Ascomycin
    C-6000 Cyclosporin A
    E-4040 Everolimus
    F-4633 Fingolimod Hydrochloride Salt
    R-5000 Rapamycin
    T-8040 Temsirolimus
    T-1377 Tofacitinib, Free Base
    T-1399 Tofacitinib,Citrate


  • The CAS number for the anhydrous form of FK-506 is given above. The CAS number for FK-506 monohydrate is 109581-93-3.
  • FK-506 (Tacrolimus) is the active ingredient in the drug sold under the trade names Fujimycin® and Prograf®. NOTE: THE FK-506 (TACROLIMUS) RESEARCH COMPOUND SOLD BY LC LABORATORIES IS NOT FUJIMYCIN® NOR PROGRAF® AND IS NOT FOR HUMAN USE.
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