| Field | Specification |
|---|---|
| Target | |
| Alternative names | Cefalexin hydrochloride monohydrate; Cephacillin hydrochloride monohydrate |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C16H20ClN3O5S |
| SMILES | |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
Cephalexin hydrochloride monohydrate, also known as Cefalexin hydrochloride monohydrate and Cephacillin hydrochloride monohydrate, is a potent, orally active semisynthetic cephalosporin antibiotic with a broad antibacterial spectrum. It has antibacterial activity against a wide variety of gram-positive and gram-negative bacteria and targets penicillin-binding proteins (PBPs) to inhibit bacterial cell wall assembly. It is used for the research of pneumonia, strep throat, and bacterial endocarditis, among others[1][2]. It has the molecular formula C16H20ClN3O5S (MW 401.87).
Physical & Chemical Properties
| CAS Number | 105879-42-3 |
|---|---|
| Molecular Formula | C16H20ClN3O5S |
| Molecular Weight | 401.87 g/mol |
| SMILES | O=C(C(N12)=C(C)CS[C@]2([H])[C@H](NC([C@H](N)C3=CC=CC=C3)=O)C1=O)O.[H]Cl.[H]O[H] |
| Target | β-lactam |
| Signaling Pathway | Anti-infection |
| Storage | Please store the product under the recommended conditions in the Certificate of Analysis. |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Literature Cited
Sources cited in this description and in the In Vitro & In Vivo Data tab. Peer-reviewed publications that used this product are listed under References.
Safety
For Research Use Only. Not for use in diagnostic or therapeutic procedures, and not for human or veterinary use. Handle in accordance with your institution's chemical hygiene plan.
In Vitro
Cephalexin (Cefalexin) hydrochloride monohydrate (10 μg/mL) interferes with biogenesis of polymer peptidoglycan (PG) by inactivating penicillin-binding proteins (PBPs)[1]. Cephalexin (Cefalexin) hydrochloride monohydrate shows broad-spectrum inhibition of gram-positive and gram-negative organisms; MIC values are 2 μg/mL for Bacillus anthracis, 2 for Edwardsiella taFda, 2 for Vibrio cholera, 2 for Pasteurella multocida, 4 for Edwardsiella tarda, 4.4 for Alcaligenes sp, and 5.7 μg/mL for Proteus rettgeri[2].
In Vivo
In male Swiss-Webster mice with bacterial infection, Cephalexin (Cefalexin) hydrochloride monohydrate (0-50 mg/kg; p.o.; for 3.5 hours) shows antibacterial activity[2].
| Animal Model | Male Swiss-Webster mice with infected bacterial[2] |
|---|---|
| Dosage | 0-50 mg/kg |
| Administration | Oral administration; for 3.5 hours |
| Result | Had antibacterial activity against Streptococcus pyogenes, Streptococcus pneumoniae, Staphylococcus aureus and several gram-negative species mice. |
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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Antibiotic Azithromycin inhibits brown/beige fat functionality and promotes obesity in human and rodents. Theranostics 2022 Jan 1;12(3):1187-1203.
Antibiotic use in early life impairs MAIT cell-mediated immunity in adulthood. J Exp Med 2026 Mar 2;223(3):e20241287. PMID: 41400657
Repositioning of the Anthelmintic Drugs Bithionol and Triclabendazole as Transthyretin Amyloidogenesis Inhibitors. J Med Chem 2021 Oct 14;64(19):14344-14357. PMID: 34547896
A novel penicillin-binding protein inhibitor with unprecedented intracellular activity eradicates multiple pathogenic bacteria. PLoS Pathog 2026 Jul 16;22(7):e1014242. PMID: 42461830
Identification and Characterization of the Neisseria gonorrhoeae MscS-Like Mechanosensitive Channel. Infect Immun 2018 May 22;86(6):e00090-18.
In Vitro Activity of β-Lactams in Combination with β-Lactamase Inhibitors against Mycobacterium tuberculosis Clinical Isolates. Biomed Res Int 2018 Jul 2:2018:3579832. PMID: 30065936
University of Texas. 2025.
bioRxiv. 2024 May 10.
Insights into the degradation mechanisms and pathways of cephalexin during homogeneous and heterogeneous photo-Fenton processes. Chemosphere 2021 Dec:285:131417. PMID: 34246101
Mass-balance-model-based evaluation of sewage treatment plant contribution to residual pharmaceuticals in environmental waters. Chemosphere 2019 Jun:225:378-387. PMID: 30884299
