Ornidazole is a potent 5-nitroimidazole derivative with antiprotozoal and antibacterial properties against anaerobic bacteria. Levo-Ornidazole is the less active isomer. Ornidazole is a approved drug that cures some protozoan infections. It has been investigated for use in Crohn's disease after bowel resection. Synthesis is a straightforward reaction between 2-methyl-nitroimidazole and epichlorohydrin under acid catalyst conditions. After passive absorption into bacterium cell, the nitro group of ornidazole is reduced to amine group by ferrodoxin type redox system. The formation of redox intermediate intracellular metabolites is believed to be the key component of microorganism killing for Ornidazole. The drug is active against anaerobic bacteria viz. Peptostreptococcus, Clostridium, B. fragilis, Prevotella, Porphyronomas, Fusobacterium and protozoa viz. E. histolytica, T. vaginalis, G. intestinalis etc.

Physicochemical Properties

Molecular Formula	C7H10CLN3O3
Molecular Weight	219.6256
Exact Mass	219.041
Elemental Analysis	C, 38.28; H, 4.59; Cl, 16.14; N, 19.13; O, 21.85
CAS #	16773-42-5
Related CAS #	Ornidazole (Levo-);166734-83-4;Ornidazole-d5;2747915-64-4;Ornidazole-13C2,15N2
PubChem CID	28061
Appearance	White to off-white solid powder
Density	1.5±0.1 g/cm3
Boiling Point	443.2±40.0 °C at 760 mmHg
Melting Point	85-90°C
Flash Point	221.9±27.3 °C
Vapour Pressure	0.0±1.1 mmHg at 25°C
Index of Refraction	1.617
LogP	0.69
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	3
Heavy Atom Count	14
Complexity	211
Defined Atom Stereocenter Count	0
SMILES	ClC([H])([H])C([H])(C([H])([H])N1C(=C([H])N=C1C([H])([H])[H])[N+](=O)[O-])O[H]
InChi Key	IPWKIXLWTCNBKN-UHFFFAOYSA-N
InChi Code	InChI=1S/C7H10ClN3O3/c1-5-9-3-7(11(13)14)10(5)4-6(12)2-8/h3,6,12H,2,4H2,1H3
Chemical Name	1-(3-Chloro-2-hydroxypropyl)-2-methyl-5-nitroimidazole
Synonyms	NSC 95075; Ro 7-0207; Tiberal
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

ADME/Pharmacokinetics	Metabolism / Metabolites Ornidazole has known human metabolites that include (2S,3S,4S,5R)-6-[1-chloro-3-(2-methyl-5-nitroimidazol-1-yl)propan-2-yl]oxy-3,4,5-trihydroxyoxane-2-carboxylic acid.
Toxicity/Toxicokinetics	Effects During Pregnancy and Lactation ◉ Summary of Use during Lactation Ornidazole is not approved for marketing in the United States by the U.S. Food and Drug Administration, but is available in other countries. The amount of ornidazole in milk is low after administration of 3 doses totaling 2 grams intravenously perinatally. Measurements of infant plasma levels during breastfeeding have not been reported. No studies have evaluated adverse effects of ornidazole on the infant during breastfeeding, but presumably they are similar to those of the closely related drug, metronidazole, such as increased risk of oral and rectal Candida infections. As with metronidazole, concern has been raised about exposure of healthy infants to ornidazole via breastmilk,[1] because of possible mutagenicity and carcinogenicity. Opinions vary among experts on the advisability of using ornidazole during longer-term therapy while breastfeeding, but avoidance of breastfeeding for 3 days after a single dose should allow milk levels to drop to negligible values because its half-life is similar to tinidazole.[2] Other drugs are available for bacterial vaginosis, and can be given vaginally, which should result in lower amounts in breastmilk. ◉ Effects in Breastfed Infants Relevant published information was not found as of the revision date. ◉ Effects on Lactation and Breastmilk Relevant published information was not found as of the revision date.
References	[1]. Ornidazole for prophylaxis of postoperative Crohn's disease recurrence: a randomized, double-blind, placebo-controlled trial. Gastroenterology, 2005. 128(4): p. 856-61. [2]. Antimicrob Agents Chemother, 1978. 14(4): p. 609-13. [3]. Clin Ther. 2017 Jul;39(7):1336-1346.
Additional Infomation	Ornidazole is a C-nitro compound that is 5-nitroimidazole in which the hydrogens at positions 1 and 2 are replaced by 3-chloro-2-hydroxypropyl and methyl groups, respectively. It is used in the treatment of susceptible protozoal infections and for the treatment of anaerobic bacterial infections. It has a role as an antiprotozoal drug, an antiinfective agent, an antibacterial drug, an antitrichomonal drug, an epitope and an antiamoebic agent. It is a member of imidazoles, a C-nitro compound, a secondary alcohol and an organochlorine compound. Ornidazole has been used in trials studying the prevention of Elective Colorectal Surgery. A nitroimidazole antiprotozoal agent used in ameba and trichomonas infections. It is partially plasma-bound and also has radiation-sensitizing action.

Solubility Data

Solubility (In Vitro)

DMSO : 44~100 mg/mL ( 200.33~455.31 mM ) Ethanol : ~44 mg/mL Water : ~2 mg/mL

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (11.38 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 (11.38 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 (11.38 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: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 2.5 mg/mL (11.38 mM) Solubility in Formulation 5: 20 mg/mL (91.06 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with ultrasonication.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	4.5531 mL	22.7656 mL	45.5311 mL
	5 mM	0.9106 mL	4.5531 mL	9.1062 mL
	10 mM	0.4553 mL	2.2766 mL	4.5531 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.