Recrystallise hydroxyurea from absolute EtOH (10g in 150mL). Note that the rate of solution in boiling EtOH is slow (15-30minutes). It should be stored in a cool dry place, but some decomposition could occur after several weeks. [Deghenghi Org Synth Coll Vol V 645 1973.] It is very soluble in H2O and can be crystallised from Et2O. [Kfod Acta Chem Scand 10 256 1956, Beilstein 3 IV 170.]
An anti-neoplastic - inhibits ribonucleoside reductase and DNA replication. A potential therapy for sickle cell anemia which involves the nitrosylation of sickle cell hemoglobin. Horseradish peroxidase catalyzes nitric oxide formation from hydroxyurea in the presence of hydrogen peroxide.
It is produced through the reaction between ethyl carbamate and hydroxylamine hydrochloride. The sodium hydroxide solution was cooled to 20-25 ℃. Add alternately under stirring of urethane and hydroxylamine hydrochloride and react at 25-28 ℃ for 16h. Use hydrochloric acid to neutralize to a pH of 6.5-7, control the temperature be not exceeding 25 ℃. Then apply concentration under reduced pressure, filtered hot and the filtrate was cooled to below 0 ℃ to precipitate our the crystal, filter, wash crystal with ice water, and dry to give crude hydroxyurea with the yield of about 65%. After refining, we can obtain pharmaceutical grade hydroxyurea.
Air & Water Reactions
Adverse reactions, contraindications and the influence of drugs
Myelosuppression was dose-limiting toxicity. Hydroxyurea may cause neutropenia and thrombocytopenia which will disappear at 1 to 2 weeks after discontinuation of the drug; sometimes there may be gastrointestinal reactions, rash, and difficulty in urinating, renal tubular injury as well as testicular atrophy and teratogenesis; there are occasional cases of symptoms of central nervous system and hair loss. It has been also reported that it can cause drug-induced fever which is reproducible under repeated administration.
Patients who have allergies, platelets being less than 50 × 109/L, chickenpox, shingles and various kinds of serious infections should be disabled. Pregnant and lactated women should also be disabled. Hydroxyurea can reduce the extent of 5-FU’s being converted into the active metabolite therefore it should be cautious when being taken together. When using hydroxyurea, we should be cautious if need to administrate barbiturates, antipsychotics and anesthetics; when hydroxyurea is combined with allopurinol, colchicine, probenecid for the treatment of gout, the dose of the above drugs should be adjusted. Avoid viral vaccination during treatment. The patients can only be subject to vaccination after discontinuing the drug for three months to one year. Upon taking hydroxyurea sheet, you should appropriately increase the fluid intake amount to increase the amount of urine and excretion of uric acid. The patients should also be subject to regular monitoring of white blood cells, platelets, blood urea nitrogen, uric acid level and inosine concentrations.
Off-White Crystalline Solid
It belongs to anti-metabolic anti-cancer drugs with its major role in the proliferation of cells in G1 and S phase. It also had delayed effect on G1/S interface. It is a cell-specific drug.
It can be applied to biochemical studies.
Through the formation of free nitric oxide, it binds to the tyrosine of the enzyme active site, leaving the nucleoside reductase inactivated. This hampers the synthesis of deoxynucleotide. It is clinically used for the treatment of chronic myelogenous leukemia as well as being used to treat metastatic ovarian cancer, head and neck primary squamous cell carcinoma and intractable psoriasis. The good belongs to anticancer drugs.
Drugs and clinical application
Hydroxyurea is a kind of anti-cancer drug for the treatment of chronic myeloid leukemia. At as early as the 1920s, it had been observed that hydroxyurea can cause the rabbits to produce megaloblastic cell similar as pernicious anemia and can inhibit leukocyte generation. In 1963 it had been found of its inhibitory effect on murine leukemia L1210. Hydroxyurea can induce bacteria to produce a toxic molecule itself to achieve the purpose of killing bacteria.
Hydroxy urea is a kind of nucleoside diphosphate reductase inhibitor and can inhibit the reduction from nucleotide to deoxynucleotide, interfering with the biosynthesis of purine and pyrimidine bases and selectively blocking the DNA synthesis. It can also cause partial inhibition of the conversion of ribonucleotides into deoxyribonucleotides. However, it has no blocking effect on RNA and protein synthesis. Hydroxyurea belongs to cycle specific drugs and is sensitive to S phase cell and can induce the hematologic remission of chronic myeloid leukemia. Compared with an alkylating agent busulfan and melphalan, it causes low incidence of secondary leukemia. The myelosuppressive effects of hydroxyurea will last for several days to several weeks which is easier to control compared with the alkylating agent.
Clinically hydroxyurea is suitable or the treatment of chronic myeloid leukemia, acute lymphocytic and acute non-lymphocytic leukemia accompanied with high cell count, idiopathic thrombocythemia, polycythemia vera, prevention of retinoic acid syndrome in acute myeloid leukemia and treatment of sickle cell anemia with frequent episodes of pain. In addition, hydroxyurea have a certain effect on the treatment of head and neck cancer, recurrent metastatic ovarian cancer, renal cancer and so on.
It appears as white needle-like crystals with the melting point being 70-72 ℃ (decomposition) or 141 ℃ (decomposition). It is easily soluble in hot water and ethanol, slightly soluble in cold ethanol, insoluble in ether, benzene. It is unstable when coming across water or heat. It is odorless and tasteless.
antineoplastic, inhibits ribonucleoside diphosphate reductase
Adult usual dose:
1. chronic myeloid leukemia, usually the starting dose is daily 20~30mg/kg body weight, take 1 times or 2 times through oral administration; when white cells counts decreases to 10 × 109/L or less, reduce the dose to about 20mg/kg body weight daily with maintained oral administration or changed to oral intermittent administration.
2 for the treatment of head and neck cancer and ovarian cancer; the dose should be 60~80mg/kg body weight each time, or ??2000~3000mg/m2 (body surface area) with oral administration once every three days. Administrate it alone or in combination with radiotherapy.
This information is edited by Xiongfeng Dai from Chemicalbook.
Flash point data for Hydroxyurea are not available; however, Hydroxyurea is probably combustible.
Odorless or almost odorless white to off-white crystalline solid. Tasteless.
An amide. Amides/imides react with azo and diazo compounds to generate toxic gases. Flammable gases are formed by the reaction of organic amides/imides with strong reducing agents. Amides are very weak bases (weaker than water). Mixing amides with dehydrating agents such as P2O5 or SOCl2 generates the corresponding nitrile. The combustion of these compounds generates mixed oxides of nitrogen (NOx).