Santacruzamate A (also known as CAY10683) is a potent and selective inhibitor of HDAC (histone deacetylase) with IC50 of 119 pM for HDAC2, it exhibits >3600-fold selectivity over other HDACs. Santacruzamate A is a cyanobacterium isolate that shares a number of structural characteristics with suberoylanilide hydroxamic acid [SAHA, trade name Vorinostat], a histone deacetylase (HDAC) inhibitor that is approved for use in clinical settings and is used to treat refractory cutaneous T-cell lymphoma. With relatively little inhibition of HDAC4 or HDAC6, both Class II HDACs, Santacruzamate A is a picomolar level selective inhibitor of HDAC2, a Class I HDAC.

Physicochemical Properties

Molecular Formula	C15H22N2O3
Molecular Weight	278.35
Exact Mass	278.163
Elemental Analysis	C, 64.73; H, 7.97; N, 10.06; O, 17.24
CAS #	1477949-42-0
Related CAS #	1477949-42-0
PubChem CID	72946782
Appearance	White to off-white solid powder
Density	1.1±0.1 g/cm3
Boiling Point	508.1±43.0 °C at 760 mmHg
Flash Point	261.1±28.2 °C
Vapour Pressure	0.0±1.3 mmHg at 25°C
Index of Refraction	1.515
Source	Cyanobacterium; Panamanian Marine Cyanobacterium; Symploca.
LogP	1.85
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	3
Rotatable Bond Count	9
Heavy Atom Count	20
Complexity	289
Defined Atom Stereocenter Count	0
SMILES	O=C(C([H])([H])C([H])([H])C([H])([H])N([H])C(=O)OC([H])([H])C([H])([H])[H])N([H])C([H])([H])C([H])([H])C1C([H])=C([H])C([H])=C([H])C=1[H]
InChi Key	HTOYBIILVCHURC-UHFFFAOYSA-N
InChi Code	InChI=1S/C15H22N2O3/c1-2-20-15(19)17-11-6-9-14(18)16-12-10-13-7-4-3-5-8-13/h3-5,7-8H,2,6,9-12H2,1H3,(H,16,18)(H,17,19)
Chemical Name	ethyl N-[4-oxo-4-(2-phenylethylamino)butyl]carbamate
Synonyms	Santacruzamate A; CAY10683; santacruzamate A; 1477949-42-0; Santacruzamate A (CAY10683); CAY10683 (SantacruzaMate A); ethyl N-[4-oxo-4-(2-phenylethylamino)butyl]carbamate; Ethyl (4-oxo-4-(phenethylamino)butyl)carbamate; CHEMBL3086767; CAY-10683; CAY 10683
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	HDAC2 ( IC50 = 119 pM ); HDAC6 ( IC50 = 434 nM )
ln Vitro	Santacruzamate A has GI50 values of 29.4 μM and 1.4 μM, respectively, and suppresses the growth of HuT-78 cutaneous T-cell lymphoma cells and HCT116 colon carcinoma cells. GI50 >100 μM indicates that Santacruzamate A is hypotoxic to human dermal fibroblast cells. [1]
ln Vivo	To further explore the role of PRMT5 and HDAC2 in CRC invasion and metastasis, researchers treated SW620 cells with inPRMT5 and inHDAC2 (CAY10683 (Santacruzamate A)). Both treatments reduced liver metastasis of CRC cells and completely inhibited the distant metastasis of SW620 cells in nude mice (Figure 6E). Altogether, our data provide compelling evidence that ZEB2 interacts with TWIST1 to recruit PRMT5 and NuRD complex to form a novel complex and epigenetically suppresses E-cadherin transcription, thereby inducing the EMT process and metastasis in CRC (Figure 7).[2] Santacruzamate A (also known as CAY10683) is a potent and specific inhibitor of histone deacetylase (HDAC), showing >3600-fold selectivity over other HDACs with an IC50 of 119 pM for HDAC2. A clinically approved histone deacetylase (HDAC) inhibitor used to treat refractory cutaneous T-cell lymphoma, suberoylanilide hydroxamic acid [SAHA, trade name Vorinostat], and Santacruzamate A share several structural features. Santacruzamate A is isolated from cyanobacterium. Santacruzamate A selectively inhibits HDAC2, a Class I HDAC, at the picomolar level while only slightly inhibiting HDAC4 or HDAC6, two Class II HDACs.
Enzyme Assay	Three HDAC isozymes (HDAC2, HDAC4, and HDAC6) have had their percent inhibition and IC50 values measured using fluorogenic HDAC assay kits and commercially available human recombinant enzyme. In a nutshell, a 96-well microtiter plate with a black bottom and flat bottom is filled with the inhibitor, and the reaction mixture is then incubated for 30 minutes at 37°C. To initiate the release of the fluorophore and stop deacetylation, the assay kit contains trichostatin A, a potent HDAC inhibitor, which is added to the bifunctional HDAC assay developer at a final reaction concentration of 1 μM. A further 15 minutes are spent incubating the reaction mixture at room temperature. A Spectra Max Gemini XPS is used to measure fluorescence. Its excitation wavelength is 360 nm, and its detection wavelength is 460 nm.
Cell Assay	HuT-78 cells were cultured in Dulbecco's modified Iscove's medium, which was enhanced with 1% L-glutamine, 1% penicillin/streptomycin, and 20% FBS. McCoy's 5A medium supplemented with 10% FBS, 1% penicillin/streptomycin, and 1% nonessential amino acids was used to cultivate HCT-116 cells. A 96-well plate was seeded with 5000 cells per well. The plates were incubated for 24 hours at 37°C with 5% CO2 prior to treatment. Using SAHA as a positive control, inhibitor treatments were incubated in wells for 72 or 96 hours. A typical MTS-PMS assay was used to measure the antiproliferative activity.
Animal Protocol	Liver Metastasis Model[2] Female BALB/c nude mice (4–5 weeks old) were used in this experiment. Mice were injected into the tail veil with cells (2 × 10~6 cells for shRNA, 8 mice/group). After 35 days, the mice were sacrificed. Liver metastatic nodules were examined macroscopically or detected in paraffin, sectioned, and stained with H&E. As for the survival assay, mice were injected into the tail veil with cells (2 × 106 cells for shRNA, 10 mice/group). As for the treating assay, mice were injected with SW620 (2 × 106 cells/mouse) injected into the tail veil (8 mice/group). After one week, CAY10683 (Santacruzamate A) (3 mg/kg) was given intravenously (i.v.) once every three days. GSK3326595 (100 mg/kg, twice daily) was given i.v. once every ten days. After 35 days, the mice were sacrificed. Then, nodules were paraffin-embedded, sectioned, and stained with H&E.
References	[1]. J Nat Prod. 2013 Nov 22;76(11):2026-33. [2]. Cancers (Basel). 2022 Jul 14;14(14):3426.
Additional Infomation	Santacruzamate A is an organooxygen compound and an organonitrogen compound. It is functionally related to a gamma-amino acid. santacruzamate A has been reported in Cyanobacterium and Symploca with data available.

Solubility Data

Solubility (In Vitro)

DMSO: ~55 mg/mL Water: <1 mg/mL Ethanol: ~55 mg/mL

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (8.98 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (8.98 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Solubility in Formulation 3: ≥ 2.5 mg/mL (8.98 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly. Solubility in Formulation 4: 5%DMSO+ 30%PEG300+ 5%Tween 80Click to Order+ 60%ddH2O: 10.0mg/ml (35.93mM)  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.5926 mL	17.9630 mL	35.9260 mL
	5 mM	0.7185 mL	3.5926 mL	7.1852 mL
	10 mM	0.3593 mL	1.7963 mL	3.5926 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.