Treatment in vivo with mezlocillin (subcutaneous injection; 1.7–5.7 mg/kg; twice daily; 7 days) resulted in suppression of delayed-type hypersensitivity reactions, IgM and IgG responses, hair loss, and decreased dosage of lymphocyte proliferation[1].

Animal/Disease Models: Male balb/c (Bagg ALBino) mouse [1]
Doses: 1.7, 4.3, and 5.7 mg/kg
Route of Administration: subcutaneous injection; 1.7, 4.3, and 5.7 mg/kg; twice (two times) daily; 7-day
Experimental Results: All dose treatments were Inhibits IgM and IgG responses as well as delayed-type hypersensitivity reactions. Hair loss was observed in most animals treated at all doses. Inhibits lymphocyte proliferation in animal spleen cell cultures.

Metabolism / Metabolites
Unlike many other penicillin-type drugs, Mezlocillin is either extensively metabolized or primarily excreted via bile, as only about 50% of the dose is detected in normal urine. Biological Half-Life 1.3 to 4.4 hours

Protein Binding
16-59%

[1]. Antibiotics and immunomodulation: effects of cefotaxime, amikacin, mezlocillin, piperacillin and clindamycin. Med Microbiol Immunol. 1985;173(5):279-89.

[2]. Mezlocillin: in vitro studies of a new broad-spectrum penicillin. Antimicrob Agents Chemother. 1977 Jan;11(1):74-9.

[3]. Treatment of accidental high dose intraventricular mezlocillin application by cerebrospinal fluid exchange. J Neurol Neurosurg Psychiatry. 1998 Mar;64(3):379-81.

Mezlocillin is a penicillin with a (2R)-2-[3-(methanesulfonyl)-2-oxoimidazolidine-1-carbamoyl]-2-phenylacetamyl group at the 6-position of its penicillin ring. It is an antibacterial drug. It is both a penicillin and a penicillin allergen. It is the conjugate acid of Mezlocillin (1-). It is a semi-synthetic ampicillin-derived acylurea penicillin. It has been proposed for the treatment of certain anaerobic bacterial infections and may be effective against inner ear, bile, and central nervous system infections. Mezlocillin has been reported in cattle and honeybees, with relevant data. Mezlocillin is a broad-spectrum β-lactam penicillin antibiotic with antibacterial activity. Mezlocillin binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of bacterial cell walls. Inactivation of PBPs interferes with the cross-linking of peptidoglycan chains, which is crucial for maintaining the strength and rigidity of bacterial cell walls. This interrupts the final stage of bacterial cell wall synthesis, leading to weakened bacterial cell walls and ultimately cell lysis.
A semi-synthetic ampicillin-derived acylurea penicillin. It has been proposed for the treatment of certain anaerobic bacterial infections and may be effective against inner ear, biliary tract, and central nervous system infections.
See also: Mezlocillin sodium (note moved to).

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Drug Indications
For the treatment of severe infections of the lungs, urinary tract, and skin caused by Gram-negative bacteria.

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Mechanism of Action
Mezlocillin inhibits the third (and final) stage of bacterial cell wall synthesis by binding to a specific penicillin-binding protein (PBP) located within the bacterial cell wall. Cell lysis is subsequently mediated by bacterial cell wall autolysins (such as autolysins); Mezlocillin may interfere with autolysin inhibitors.

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Pharmacodynamics
Mezlocillin is a penicillin-type β-lactam antibiotic used to treat bacterial infections caused by susceptible bacteria, typically Gram-positive bacteria. The name "penicillin" can refer to several existing penicillin derivatives or to a class of antibiotics derived from penicillin. Mezlocillin exhibits in vitro activity against Gram-positive, Gram-negative aerobic, and anaerobic bacteria. Mezlocillin's bactericidal activity stems from its inhibition of cell wall synthesis and its action through binding to penicillin-binding proteins (PBPs). Mezlocillin is stable against the hydrolytic activity of various β-lactamases, including penicillinase, cephalosporinase, and extended-spectrum β-lactamases. Mezlocillin can be used to treat Mezlocillin-sensitive strains of Haemophilus influenzae, Klebsiella spp., Pseudomonas spp., Proteus mirabilis, and Escherichia coli. Escherichia coli, Enterobacter spp., Enterococcus faecalis, Peptococcus spp., Peptostreptococcus spp., Bacteroides spp. (including Bacteroides fragilis), Morganella morganii, Serratia spp., Neisseria gonorrhoeae, Proteus vulgaris, and Providencia reticularis. This drug has been discontinued in the United States.

C21H25N5O8S2

539.581902265549

539.114

51481-65-3

Mezlocillin sodium;42057-22-7

656511

Typically exists as solid at room temperature

1.6±0.1 g/cm3

655.5ºC at 760 mmHg

350.2ºC

1.701

-1.18

3

9

6

36

1080

4

O=C([C@@H](C(C)(C)S[C@]1([H])[C@@H]2NC([C@H](NC(N3CCN(S(=O)(C)=O)C3=O)=O)C4=CC=CC=C4)=O)N1C2=O)O

YPBATNHYBCGSSN-VWPFQQQWSA-N

InChI=1S/C21H25N5O8S2/c1-21(2)14(18(29)30)26-16(28)13(17(26)35-21)22-15(27)12(11-7-5-4-6-8-11)23-19(31)24-9-10-25(20(24)32)36(3,33)34/h4-8,12-14,17H,9-10H2,1-3H3,(H,22,27)(H,23,31)(H,29,30)/t12-,13-,14+,17-/m1/s1

(2S,5R,6R)-3,3-dimethyl-6-[[(2R)-2-[(3-methylsulfonyl-2-oxoimidazolidine-1-carbonyl)amino]-2-phenylacetyl]amino]-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)