| Exploration stage | Metallurgical test purpose | Research on ore material composition | Ore characteristics | Degree of test | Metallurgical sample requirements |
| Census | Assess whether ore can be used as an industrial raw material | initial research | Easy dressing stone | Analogy evaluation, no experiment | |
| General ore | Optional (melting) test | The optional test sample weighs approximately 50-500 kg. | |||
| Difficult to choose ore | Optional (melting) test and laboratory process test | ||||
| Detailed investigation | Evaluate whether the deposit has industrial value. | Detailed study | Easy ore | Optional (melting) test | The laboratory process combination weighs 300-1000 kg. The laboratory expanded the continuous test sample 5-25t. |
| General ore | Laboratory process test | ||||
| Difficult to choose ore | Laboratory process test and laboratory extended continuous test | ||||
| exploration | Provide mine development feasibility study and design basis | In-depth study | Easy ore | Laboratory process test | The sample collection, test conditions and test contents are jointly determined by the geological, experimental and design units. |
| General ore | Laboratory expansion of continuous trials | ||||
| Difficult to choose ore | Semi-industrial test |
Pyrimidine series intermediates
Pyrimidine, also known as 1,3-diazepine, is a heterocyclic compound with the chemical formula C4H4N2. Pyrimidine is formed by replacing 2 carbons in the meta-position of benzene with 2 nitrogen atoms, and is a diazine. Like pyridine, pyrimidine retains its aromaticity.
Introduction
Name: Pyrimidine
Molecular formula: C4H4N2
Molar mass: 80.09 g/mol
Density: 1.016 g/ml
Melting point: 20 - 22 °C
Boiling point: 123 - 124 °C
CAS Number: 289-95-2
EINECS Number: 206-026-0
SMILES: C1=NC=NC=C1
Application
(1) Anticancer drugs. In the selection of anticancer substances, it is crucial that there are significant differences between tumor tissues and normal tissues, that is, they have a certain ability to recognize target cells. Porphyrin compounds have special affinity for cancer cells due to their unique structures, and they can selectively stay in cancer tissues. The research of it as a localizing agent and a drug for diagnosis and treatment of cancer has already aroused great interest of chemists, medical scientists and biologists. 5-Fluorouracil is a widely used anti-metabolite and anti-tumor drug in clinic. It has inhibitory effect on various tumors. It has good clinical effect in the treatment of colorectal cancer, gastric cancer, breast cancer and other cancers. Polyesters, polyester hydrocarbons, polyester amides, deoxyribonucleic acid, furans, 5-fluorouracil derivatives linked to nitroxide radicals all have antitumor effects.
(2) Anti-AIDS drugs. Viral diseases have become one of the most harmful diseases to human beings, especially the spread of AIDS, which has aroused widespread concern. There are many kinds of anti-AIDS drugs that have been approved by the US Food Administration (FDA), many of which are nucleoside compounds. In order to reduce the toxicity of drugs and improve their efficacy, scientists have begun to turn their attention to the study of non-nucleoside compounds, and such compounds have become the focus of antiviral drug research.
Synthetic method
Pyrimidines and various substituted pyrimidines are synthesized in a variety of ways. For example, barbituric acid (2,4,6-trihydroxypyrimidine) can be obtained by the condensation of urea and diethyl malonate under the action of sodium alkoxide. Barbituric acid and phosphorus oxychloride are heated together to obtain 2,4,6-trichloropyrimidine, which reacts with sodium methoxide to obtain trimethoxypyrimidine. Chloropyrimidines react with ammonia or primary and secondary amines to generate the corresponding aminopyrimidines. The derivatives of pyrimidine, cytosine, uracil and thymine, are the constituent parts of nucleic acid and deoxynucleic acid, and the pyrimidine part in the vitamin B1 molecule is a 4-amino-2-methyl-5-pyrimidine methyl group. Many oral long-acting sulfa drugs are derivatives of pyrimidine and its isomers.
The 2,4-dichloropyrimidine is prepared by reduction reaction in the presence of palladium, magnesium oxide and activated carbon.
Pyrimidine Series Intermediates,2-Chloro-5-Methylpyrimidine,5-Bromo-2-chloropyrimidine,2 4-Dichloro-5-Methylpyrimidine
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