Inhibitor of DNA synthesis. [2]

When exposed to diazoserine (100 μg/mL for six hours), certain organisms experience morphological changes, such as the characteristic elongation of Candida albicans cells [2]. Azaserine (0–10 μM) stops E. coli from growing. coli strains for UTH 4, UTH 7036, UTH 7048, and UTH 7049 having MIC values of 12.11, 51.9, 69.2, and 69.2 μg/mL [3].

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Azaserine, as an inhibitor of DNA synthesis, caused a specific type of morphological change in the sensitive organism Candida albicans. When C. albicans cells were inoculated into a liquid medium (composition: 1% malt extract, 0.1% yeast extract, 0.3% sucrose) at a concentration of 10⁵-10⁶ cells/ml and incubated for 6 hours with azaserine at a concentration above 100 μg/ml, the cells exhibited characteristic elongation. [2]

Rats given intraperitoneal injections of diazoserine (5 mg/kg) once or twice a week for six months develop tumors [1].

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In mouse L1210 leukemia cells growing in culture, azaserine (25 μM for 4 hours) inhibits FGAM synthetase and glucosamine-6-phosphate isomerase. This leads to a blockade in de novo purine biosynthesis and affects nucleotide sugar metabolism. [5]
Treatment with azaserine results in a massive accumulation of FGAR (N-formylglycineamide ribotide) and its di- and triphosphate derivatives (FGAR-DP and FGAR-TP). Four hours after exposure to 25 μM azaserine, the cellular concentration of FGAR triphosphate reaches 9.5 mM, which is nearly 3-fold higher than the normal concentration of ATP in mammalian cells (∼3.5 mM). [5]
Azaserine causes significant depletion of guanine nucleotides (GTP, GDP) and adenine nucleotides (ATP, ADP) in L1210 cells. After 4 hours of treatment with 25 μM azaserine, ATP levels were 39% of control, ADP 29%, GTP 21%, and GDP 49%. [5]
Azaserine affects pyrimidine nucleotide levels, with UTP at 67% of control, UDP at 66%, and CTP at 50% of control. UDP-Glc/Gal levels were maintained at 100% of control, while UDP-GlcNAc/GalNAc levels declined to 34% of control, consistent with inhibition of glucosamine-6-phosphate isomerase. [5]
Unlike acivicin and DON, azaserine does not appear to significantly inhibit CTP synthetase in growing cells, as the ratio of CTP to UTP remains approximately the same as in control cultures. [5]
Azaserine treatment causes an accumulation of UTP relative to ATP levels, demonstrating "complementary stimulation" of the de novo pyrimidine pathway when the purine pathway is blocked. [5]

Yeast Cell Morphology Assay: Candida albicans IAM 4888 cells were inoculated into a liquid medium containing 1% malt extract, 0.1% yeast extract, and 0.3% sucrose. The initial cell concentration was approximately 10⁵ to 10⁶ cells per milliliter. Azaserine was added to the culture at a concentration of 100 μg/ml. The culture was then incubated for 6 hours. After incubation, the morphological changes of the yeast cells, specifically cell elongation, were observed under a light microscope. [2]

Animal/Disease Models: Wistar rat[1]
Doses: 5 mg/kg
Route of Administration: intraperitoneal (ip) injection; 5 mg/kg once or twice a week for 6 months
Experimental Results: After 1 year, most of the treated rats The rat pancreas was diffusely abnormal and contained numerous hyperplastic nodules and adenomas, and more than one-quarter of the rats developed pancreatic cancer.

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Absorption, Distribution and Excretion
Veterinary: Poor oral absorption. …After treatment of rats with (3)H-azaseline, the pancreas has been shown to reach high levels of radioactivity.

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Interactions
This study evaluated the chemopreventive effects of synthetic retinoids, selenium, and their combination in the post-initiation phase of azaserine-induced carcinogenesis in rats. Male Lewis rats were injected weekly with 30 mg/kg azaserine for 3 weeks, while being fed a purified diet. One week after the end of carcinogen treatment, the rats were divided into groups and fed diets supplemented with one of the following three purified diets: 0.5 or 1 mmol/kg of retinoid N-(2-hydroxyethyl) retinamide; 5 ppm sodium selenite; or a combination of retinoids and selenium. One year after the diet change, the incidence of pancreatic cancer and other tumors was determined by necropsy and histological studies. In the control group not treated with retinoids, the incidence of pancreatic cancer (including carcinoma in situ, CIS) was 68%. Because the dietary supplements were administered after the end of carcinogen exposure, their effects on pancreatic and hepatocellular carcinoma occurred in the post-initiation phase of carcinogenesis. Consistent with previous studies, retinoids inhibited the progression of pancreatic cancer in a dose-dependent manner. Selenium alone was ineffective. However, retinoids combined with selenium were more effective than retinoids alone, although the enhancement of the inhibitory effect was not significant. The study also found that retinoids could inhibit liver cancer induced by serine azacitidine. Selenium, whether used alone or in combination with retinoids, was ineffective. This study investigated the effects of dietary intake of fish oil (herring oil) and fish protein (cod protein) on the development of pancreatic precancerous lesions in male Wistar rats. 14-day-old rats were given a single intraperitoneal injection of 30 mg/kg body weight of L-serine azacitidine (diazoacetic acid serine ester). These animals received a 4-month dietary treatment after weaning at 21 days of age. Compared with casein as a protein source, fish protein did not appear to produce a significantly different precancerous response. However, compared with a diet rich in 20% corn oil and omega-6 fatty acids, a diet rich in 20% herring oil and omega-3 fatty acids significantly reduced the size and number of precancerous lesions. This study suggests that fish oil rich in omega-3 fatty acids may have the potential to inhibit cancer development. In rats, chicks, and geese fed a diet containing raw soy products, decreased food intake and growth rate, pancreatic enlargement, excessive secretion of digestive enzymes, and enlargement of intestinal segments and their contents were observed. These effects were associated with the concentration of trypsin inhibitors in the diet. Long-term studies have shown that the incidence of pancreatic nodules is related to the level of trypsin inhibitors in the diet. Feeding raw soy products enhances the carcinogenic effects of azaserine, and feed containing raw soy products increases the incidence and size of pancreatic nodules in rats. This study investigated the effects of coffee and dietary fat (alone or in combination) on the development of precancerous lesions in the exocrine pancreas of rats and hamsters treated with azaserine or N-nitrosobis(2-oxopropyl)amine, respectively. For one week after carcinogen treatment, animals were fed the corresponding diets (5% or 25% corn oil) and coffee (in lieu of drinking water), respectively. Four months after treatment, quantitative examination of the pancreas was performed to determine the number and size of precancerous lesions. In rats, coffee intake alone inhibited the growth of eosinophilic lesions and slightly suppressed the positive regulatory effect of fat on these lesion growth, suggesting a negative rather than positive interaction between these two lifestyle factors. In hamsters, coffee intake alone promoted the growth of cystic lesions, while fat intake alone promoted the growth of ductal lesions. The effects of fat and coffee on pancreatic cancer development in hamsters remain inconclusive. For more complete data on interactions of AZASERINE (8 species), please visit the HSDB records page.

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Azaserine shows limited growth inhibitory activity in mouse L1210 leukemia cell culture. At a concentration of 5 μM, cellular growth was reduced to less than 60% of control cultures. However, increasing the concentration up to 100 μM did not further inhibit growth beyond 50%, and an IC50 value could not be determined. [5]
The greater accumulation of FGAR derivatives (particularly FGAR triphosphate, reaching 9.5 mM) induced by azaserine may lead to greater host toxicity compared to other glutamine antagonists. These metabolites may interfere with RNA synthesis in nondividing cells, possibly explaining the higher systemic toxicity observed with this drug. [5]
It is known from previous studies (referenced in the article) that azaserine induces morphological irregularities in the genetic material of malignant and normal cells, with associated increases in cellular size and DNA content. [5]
The potential incorporation of FGAR triphosphate into nucleic acids or direct inhibition of RNA or DNA polymerases by FGAR derivatives may represent additional mechanisms of cytotoxicity. [5]

[1]. Longnecker DS, Curphey TJ. Adenocarcinoma of the pancreas in azaserine-treated rats. Cancer Res. 1975 Aug;35(8):2249-58.

[2]. Screening of Antifungal Antibiotics According to Activities Inducing Morphological Abnormalities. Agric. Biol Chem., 47 (9), 2061-2069, 1983.

[3]. Williams MV, Tritz GJ. Studies on the modes of action of azaserine inhibition of Escherichia coli. Potentiation of phenylalanine reversal. J Antimicrob Chemother. 1977 Jan;3(1):65-77.

[4]. Azaserine, DON, and azotomycin: three diazo analogs of L-glutamine with clinical antitumor activity. Cancer Treat Rep. 1979 Jun;63(6):1033-8.

[5]. Cytotoxic mechanisms of glutamine antagonists in mouse L1210 leukemia. J Biol Chem. 1990 Jul 5;265(19):11377-81.

Azaserine to an independent committee of scientific and health experts, azaserine may be carcinogenic. Azaserine is a pale yellow to green crystalline substance used as an antifungal agent. It is a carboxylic acid ester formed by the condensation of the carboxyl group of diazonium acetic acid with the hydroxyl group of L-serine. It is an antibiotic produced by Streptomyces and possesses multiple functions including antibacterial, antitumor, antifungal, anti-metabolic, immunosuppressive, metabolic, and glutamine antagonistic effects. It is a diazo compound, a carboxylic acid ester, an L-serine derivative, and a non-protein L-α-amino acid. Azaserine has been reported to exist in Streptomyces, and relevant data are available. Azaserine is a naturally occurring serine derivative diazo compound with antitumor properties. Azaserine acts as a purine antagonist and glutamine analog (glutamine aminotransferase inhibitor), competitively inhibiting the glutamine metabolic pathway. Azaserine is an antibiotic and antitumor drug, currently undergoing clinical trials as a potential antitumor agent. (NCI04)
An antibiotic substance produced by various Streptomyces species. It is an inhibitor of glutamine-associated enzyme activity and can be used as an antitumor drug and immunosuppressant.

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Mechanism of Action
Amino acid antagonists inhibit protein and nucleic acid synthesis by interfering with the incorporation of specific amino acids required for protein or nucleic acid synthesis. These compounds include… azacelin….
Glutamine…/antagonist/azacelin…is a potent…/inhibitor/ of the de novo purine nucleotide synthesis pathway.
...Inhibits purine biosynthesis by forming a covalent bond with cysteine residues at the active site of a key enzyme in the pathway—formylglycamide ribopeptidase.
Veterinary: Inhibition of glutamine utilization in asparagine biosynthesis, intravenous or intraperitoneal injection enhances the efficacy of L-asparaginase against experimental solid tumors. ...Antidiuretic effects were observed in mice.
Four cell lines containing γ-glutamyl transpeptidase have been established. /A/ A positive correlation was observed between cellular gamma-glutamyl transferase (GGT) levels and susceptibility to azaserin toxicity. Strains with the lowest GGT activity exhibited the strongest resistance to azaserin toxicity.

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Therapeutic Uses
Antibiotics, antifungals; Antibiotics, antitumor drugs; Antimetabolites; Antitumor drugs; Carcinogens; Immunosuppressants
Glutamine antagonist azaserin…when used alone, it exhibits only weak cytosolic inhibitory activity…but its activity is significantly enhanced when used in combination with purine analogs such as mercaptopurine or thioguanine.
Azaserine has been tested as a purine synthesis inhibitor and in combination with mercaptopurine for the treatment of acute childhood leukemia.
Veterinary Uses: Due to the replacement by more effective drugs, it has been used as an antimetabolite in a few experimental cases for the treatment of tumors.
For more data on therapeutic uses (complete) for information on AZASERINE (of 6), please visit the HSDB records page.

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Drug Warning
Veterinarian: Use of this product may cause fetal toxicity... The line between effective and toxic doses is very narrow.

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In this study, azaserine was used as one of several known antifungal antibiotics to establish a reference library of morphological changes induced in fungi and yeasts. This library served as a standard for screening new microbial products with potential selective modes of action. The characteristic elongation of C. albicans cells caused by azaserine was noted as a distinct morphological abnormality associated with inhibitors of DNA synthesis. [2]

C5H7N3O4

173.12678

173.043

115-02-6

460129

White to yellow solid powder

146-162° (dec)

-1.37

2

6

5

12

233

1

C([C@@H](C(=O)O)N)OC(=O)C=[N+]=[N-]

MZZGOOYMKKIOOX-VKHMYHEASA-N

InChI=1S/C5H7N3O4/c6-3(5(10)11)2-12-4(9)1-8-7/h1,3H,2,6H2,(H,10,11)/t3-/m0/s1

(S)-2-amino-3-(2-diazoacetoxy)propanoic acid

CN-15757 P165 O-Diazoacetyl-L-serine P-165 CL-337P 165CL337diazoacetate (ester) LSerine diazoacetylserine serine diazoacetate AZAS AZS

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

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

H2O : ~50 mg/mL (~288.80 mM)

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.)