Biochemical

A compound that can target cells expressing the estrogen receptor (ER), and produce predominantly 3-MeA adducts in those cells has been designed and synthesized. This compound produces mainly the 3-MeA adduct upon reaction with calf thymus DNA, and binds to the ER with a relative binding affinity of 51% (estradiol = 100%). The compound is toxic to ER-expressing MCF-7 breast cancer cells, and pre-treatment with the ER antagonist fulvestrant abrogates the toxicity. Pre-treatment of MCF-7 cells with netropsin, which inhibits N3-adenine methylation by the compound, resulted in a threefold decrease in the toxicity. These results demonstrate the feasibility of this strategy for producing 3-MeA adducts in targeted cells [1].

Absorption, Distribution and Excretion
In rats, approximately 30% of the injected radioactive material (in the form of 14CH3 methanesulfonate) is excreted as 14CO2 within 30 hours, with another 20% recovered in the urine. In mice, approximately 34% is recovered in the urine after a single intraperitoneal injection, and 27% is recovered as 14CO2. In both mice and rats, methanesulfonate is rapidly distributed throughout the body, including the central nervous system. In pregnant rats (day 21 of gestation), it crosses the placenta into the fetus within 2 minutes of intravenous injection. Two hours after intravenous injection of 100 mg/kg body weight of methanesulfonate in rats, methanesulfonate was undetectable in serum. …If administered intraperitoneally, it rapidly enters the excretory system in its activated form.

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Metabolisms/Metabolites
In the first 16 hours following intravenous injection of (14) CH3-methylmethanesulfonate, multiple metabolites (methylthiouric acid sulfoxide, 2-hydroxy-3-methylsulfinylpropionic acid, methylsulfinylacetic acid, and a mixture of methylthiouric acid and N-(methylthioacetyl)glycine) were detected in rat urine. These metabolites, accounting for approximately 80% of excreted radioactivity, are a result of the initial methylation of cysteine residues by the methanesulfonate.

Interactions
This study investigated the combined effects of methyl methanesulfonate and ethyl methanesulfonate on the induction of 6-thioguanine resistance mutants and chromosomal aberrations in Chinese hamster V79 cells. Cells were simultaneously treated with ethyl methanesulfonate at a concentration of D20/SRP (D20 being the concentration required to reduce cell viability to 20%) and different concentrations of methyl methanesulfonate for 3, 6, or 9 hours. In other experiments, cells were simultaneously treated with methyl methanesulfonate at a concentration of D20 and different concentrations of ethyl methanesulfonate for 3, 6, or 9 hours. Mathematical analysis of the combined effects of the two chemicals on cell killing (cytotoxicity) and 6-thioguanine resistance mutations showed that methyl methanesulfonate and ethyl methanesulfonate exhibited synergistic effects in both cell killing and mutation induction. Simultaneous treatment with methyl methanesulfonate at a concentration of D20 and different concentrations of ethyl methanesulfonate for 3 hours induced a cumulative effect on the frequency of induced chromosomal aberrations. However, treatment with ethyl methanesulfonate at concentration D20 and different concentrations of methyl methanesulfonate for 3 hours did not significantly differ from the frequency of chromosomal aberrations induced by methyl methanesulfonate alone. Ethanol itself did not induce any significant chromosomal aberrations in hamster ovary cells. However, posttreatment with ethanol enhanced methyl methanesulfonate-induced chromosomal aberrations. Chromatid exchange was primarily increased in cultures treated with methyl methanesulfonate followed by ethanol. ... Posttreatment with acetaldehyde, the main metabolite of ethanol, also enhanced methyl methanesulfonate-induced chromosomal aberrations. ... The main aberration types enhanced by acetaldehyde posttreatment were similar to those enhanced by ethanol posttreatment. /Methyl Methanesulfonate/

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Non-human Toxicity Values
Oral LD50 in rats: 225 mg/kg
Intraperitoneal LD50 in rats: 140 mg/kg
Subcutaneous LD50 in rats: 125 mg/kg
Intravenous LD50 in rats: 175 mg/kg

[1]. Bioorg Med Chem. 2011 Sep 1;19(17):5093-102.

According to an independent committee of scientific and health experts, methyl methanesulfonate may be carcinogenic. Methyl methanesulfonate is a colorless to amber liquid. (NTP, 1992) Methyl methanesulfonate is a methanesulfonate ester formed by the condensation of methanesulfonic acid and methanol. It is an alkylating agent, genotoxin, carcinogen, mutagen, and apoptosis inducer. Methyl methanesulfonate is a stable, colorless, flammable liquid that releases toxic sulfoxide fumes when heated and decomposes. Methyl methanesulfonate is used as a catalyst in chemical synthesis in the laboratory and has been tested clinically as a chemotherapy drug for cancer. This substance is an alkylating agent that can exert mutagenic effects by altering and damaging DNA, and is therefore reasonably expected to be a human carcinogen. (NCI05) An alkylating agent used in cancer treatment, it may also act as a mutagen by interfering with and damaging DNA.

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Mechanism of Action
Monofunctional methylating agents, such as methyl methanesulfonate, primarily produce 7-methylguanine, an adduct that is considered harmless because it does not block nucleic acid synthesis or cause mis-incorporation of bases into newly synthesized DNA. However, this altered base is considered to have indirect detrimental effects on cells because the increased instability of the glycosyl bonds leads to the formation of undirected depurination sites in the DNA template. Another common source of damage is 3-methyladenine. This product has been shown to block nucleic acid synthesis, but direct evidence that it is lethal in mammalian cells is lacking. The main mutagenic damage from methylating agent formation is O6-methylguanine and O4-methylthymine, both of which can lead to base transposition in newly synthesized DNA. O6-methylguanine is formed in greater quantities than O4-methylthymine, and it has been shown that guanine with an adenine 5' end is twice as likely to be methylated at the O6 position as guanine with a thymine 5' end, indicating that the base sequence influences adduct formation. Another type of damage caused by methylating agents is methyltriphosphate. This persistent adduct significantly slows nucleic acid synthesis in cell-free systems, but its effects on intracellular gene expression or mutagenesis remain unclear. …Long-chain alkylating agents produce similar damage profiles, but the relative proportions of the adducts formed differ significantly. The largest amount of damage formed is alkyltriphosphate, accounting for more than 50% of total DNA damage. Under the influence of these drugs, O4-alkylthymine, a promutogenic agent, becomes increasingly important. Its production is 5 to 10 times higher than that of methylating agents, and although it is slowly cleared from DNA, its half-life is significantly longer than that of O6-alkylguanine, making it potentially more important in inducing point mutations after DNA synthesis.

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Drug Warning
A study of 13 cancer patients treated for up to 350 days with total doses ranging from 2.8 to 800 mg/kg body weight showed significant gastrointestinal and hepatotoxic reactions.

C2H6O3S

110.13

110.003

66-27-3

Methyl methanesulfonate-d3;91419-94-2

4156

Colorless to light yellow liquid

1.2±0.1 g/cm3

202.1±9.0 °C at 760 mmHg

20ºC

104.4±0.0 °C

0.4±0.4 mmHg at 25°C

1.406

-0.57

0

3

1

6

105

0

S(C([H])([H])[H])(=O)(=O)OC([H])([H])[H]

MBABOKRGFJTBAE-UHFFFAOYSA-N

InChI=1S/C2H6O3S/c1-5-6(2,3)4/h1-2H3

methyl methanesulfonate

METHYL METHANESULFONATE; 66-27-3; Methyl mesylate; Methanesulfonic acid methyl ester; Methylmethanesulfonate; methylmethane sulfonate; Methanesulfonic acid, methyl ester; Methyl methanesulphonate;

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)

DMSO: 100 mg/mL (908.02 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (22.70 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.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (22.70 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.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (22.70 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.

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