(1S)-Calcitriol (1α,25-Dihydroxy-3-epi-vitamin-D3) is a natural metabolite of 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3). (1S)-Calcitriol displays potent vitamin D receptor (VDR)-mediated effects, such as inhibition of keratinocyte growth or parathyroid hormone secretion.

Physicochemical Properties

Molecular Formula	C27H44O3
Molecular Weight	416.636
Exact Mass	416.329
CAS #	61476-45-7
Related CAS #	Calcitriol;32222-06-3
PubChem CID	5283736
Appearance	White to off-white solid powder
LogP	5.1
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	3
Rotatable Bond Count	6
Heavy Atom Count	30
Complexity	688
Defined Atom Stereocenter Count	6
SMILES	C12(C([H])([H])C([H])([H])C([H])([H])/C(=C(\C(=C3/C(C(C(C(O[H])([H])C/3([H])[H])([H])[H])(O[H])[H])=C([H])[H])\[H])/[H])/C1(C(C(C2(C(C(C(C(C(O[H])(C([H])([H])[H])C([H])([H])[H])([H])[H])([H])[H])([H])[H])(C([H])([H])[H])[H])[H])([H])[H])([H])[H])[H])C([H])([H])[H]
InChi Key	GMRQFYUYWCNGIN-GNVXBELXSA-N
InChi Code	InChI=1S/C27H44O3/c1-18(8-6-14-26(3,4)30)23-12-13-24-20(9-7-15-27(23,24)5)10-11-21-16-22(28)17-25(29)19(21)2/h10-11,18,22-25,28-30H,2,6-9,12-17H2,1,3-5H3/b20-10+,21-11-/t18-,22+,23-,24+,25+,27-/m1/s1
Chemical Name	(1S,3S,5Z)-5-[(2E)-2-[(1R,3aS,7aR)-1-[(2R)-6-hydroxy-6-methylheptan-2-yl]-7a-methyl-2,3,3a,5,6,7-hexahydro-1H-inden-4-ylidene]ethylidene]-4-methylidenecyclohexane-1,3-diol
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 Note: (1). This product requires protection from light (avoid light exposure) during transportation and storage.(2). Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture.
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

ln Vitro	3‐epi‐Calcitroic acid is the final product of rat CYP24A1's metabolism of (1S)‐Calcitriol (1α,25‑Dihydroxy‑3‑epi‑vitamin‑D3; 3‑epi‑1a,25(OH)2D3)[1].
References	[1]. Metabolic stability of 3-epi-1α,25-dihydroxyvitamin D3 over 1 α 25-dihydroxyvitamin D3: metabolism and molecular docking studies using rat CYP24A1. J Cell Biochem. 2013 Oct;114(10):2293-305.

Solubility Data

Solubility (In Vitro)

DMSO: 100 mg/mL (240.02 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (6.00 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 (6.00 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 (6.00 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.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.4002 mL	12.0008 mL	24.0015 mL
	5 mM	0.4800 mL	2.4002 mL	4.8003 mL
	10 mM	0.2400 mL	1.2001 mL	2.4002 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.