Patent Description:
Hypoxia inducible factor (HIF) was first discovered by Semenza and Wang in <NUM>. It is a transcriptional regulator that is universal in human cells and participates in the regulation of various physiological functions of the body. At present, it has been confirmed that more than <NUM> genes are regulated by HIF, and the encoded products produced by regulation, including erythropoietin (EPO), inducible nitric oxide synthase (iNOS), transferrin, vascular endothelial growth factor (VEGF) and the like, play an important role in erythropoiesis, blood vessel growth, tumor growth, as well as metabolism and cell differentiation.

HIF is a heterodimer composed of α subunit (HIF-α) and β subunit (HIF-β). There are three main subtypes: HIF-<NUM>, HIF-<NUM>, and HIF-<NUM>. Among them, the α subunits are different, which are functional subunits, and determine the biological activity of HIF. The expression of their activity level is affected by oxygen content. They cannot exist stably in cells with normal oxygen content, with a half-life of only <NUM>, and, only under hypoxic conditions can they stably exist and then play a role. Whereas, the β subunits are the same, which are structural subunits, and their protein expression is not affected by oxygen content.

Prolyl hydroxylase (PHD) belongs to the dioxygenase superfamily and is a Fe<NUM>+, <NUM>-oxoglutarate-dependent oxygenase. At present, <NUM> subtypes have been found, namely PHD1, PHD2, PHD3 and PHD4. There are many studies on the first three. PHD1 is expressed in the nucleus, PHD2 is expressed in the cytoplasm, and PHD3 is expressed in both the nucleus and the cytoplasm. Current studies have found that HIF-α is a substrate of PHD. PHD is one of important regulators of HIF pathway, and is a rate-limiting enzyme of HIF degradation. Under normal oxygen content, it can recognize proline residues Pro402 and Pro564 on HIF-α, to make them hydroxylated, and then ubiquitinated to degrade HIF-α through the mediation of Hippel Lindau protein. However, under hypoxic conditions, the hydroxylation activity of PHD decreases, which hinders the degradation of HIF-α, and causes accumulation and stable expression of HIF-α, so that it is possible to improve heart failure, ischemia, tissue injury and other diseases in patients with anemia, heart disease and kidney disease.

EPO is synthesized and released by the kidney tissue, which can promote the production of red blood cells in the cells, stimulate the hematopoietic function of bone marrow, and improve the state of hypoxia. At present, EPO and recombinant EPO are mainly used to treat anemia caused by chronic kidney disease, cancer chemotherapy and the like. Increasing the level of EPO in the body is of great significance for the improvement of anemia symptoms. The problems of clinical use of EPO include: <NUM>. it is easy to exceed the physiological range of EPO and cause cardiovascular damage; <NUM>. the convenience of injection is poor; <NUM>. there are immunogenic problems and there are certain risks.

By inhibiting PHD, and reducing the degradation of HIF, it is possible to accumulate the expression of HIF and promote the endogenous secretion of EPO, to maintain its level within the physiological range, thereby improving the hematopoietic function of cells. Therefore, the development of small molecule HIF-PHD inhibitors is of great significance for the treatment of renal anemia caused by insufficient secretion of EPO or even inability to synthesize it in the kidney.

So far, some HIF-PHD inhibitors have been developed. Among them, Roxadustat from Fibrogen is in the pre-registration stage. Vadadustat from Akebia Therapeutics, Daprodustat from GlaxoSmithKline and Molidustat from Bayer are in phase III clinical studies. <CIT> disclosed a HIF inhibitor of <NUM>-hydroxyl-<NUM>,<NUM>-naphthyridine substituted by aryloxy or heteroaryloxy. <CIT> disclosed HIF inhibitors based on isoquinolines.

There is still an urgent need to develop small molecule HIF-PHD inhibitors with novel structures, better efficacy and better safety.

The present disclosure provides a type of HIF-PHD inhibitor compounds with novel structures, which can be used to the treatment of various HIF-related and/or EPO-related diseases or conditions, such as heart failure, ischemia, tissue injury and the like in patients with anemia, heart disease and kidney disease.

The current invention relates to the following items:.

Preferably, R<NUM> is selected from phenyl or pyridyl, optionally substituted with one or more substituents, or is selected from Ci-Ce alkyl. More preferably, R<NUM> is selected from phenyl or pyridyl, optionally substituted with halogen, hydroxy, Ci-Ce alkoxy or halogen-substituted C<NUM>-C<NUM> alkyl or R<NUM> is selected from C<NUM>-C<NUM> alkyl.

In formula (V)
R<NUM>', R<NUM>', R<NUM>', R<NUM>', Rs' are preferably H, OH, halogen, C<NUM>-C<NUM> alkyl, C<NUM>-C<NUM> alkoxy, halogen-substituted C<NUM>-C<NUM> alkyl.

The compound of the present disclosure containing OH and COOH moieties may have a prodrug forming moiety linked to it (not according to the current invention). The prodrug forming moiety is removed by metabolism, and the compound with free hydroxyl or carboxylic acid is released in the body. Prodrug can effectively adjust the pharmacokinetic properties of the compound, such as solubility and lipid-water distribution coefficient, absorption in the gastrointestinal tract, bioavailability, tissue permeability and clearance rate.

Such compounds are represented by structural formula (Ib) (not according to the current invention):
<CHM>.

Preferably, R<NUM> is selected from C<NUM>-C<NUM> alkyl (C=O)O-C<NUM>-C<NUM> alkyl-, more preferably C<NUM>-C<NUM> alkyl (C=O)O-C<NUM>-C<NUM> alkyl-, for example, t-butyl-(C=O)O-CH<NUM>-.

The following method for the preparation of compound I serves illustrative purposes only and is not according to the current invention:
<CHM>.

The compound of formula II, the method can also be implemented by the following scheme <NUM>. Steps <NUM>-<NUM> of this method serve illustrative purposes only. Steps <NUM> and <NUM> are according to the current invention:
<CHM>.

For the compound of formula IIIa, the method can also be implemented by the following scheme <NUM> (this scheme <NUM> serves illustrative purposes and is not according to the current invention):
<CHM>.

Preferably, for the compound of formula IV, the method can also be implemented by the following scheme <NUM>:.

Wherein the intermediate M12 can be obtained through the afore-mentioned steps or is commercially available.

For example, intermediate M12 can be obtained through steps <NUM>-<NUM> in the afore-mentioned scheme <NUM>.

In the above schemes, preferably, X<NUM> is selected from halogen, such as F, Cl, Br, I; the halogenation reagent Li is selected from N-bromosuccinimide, N-chlorosuccinimide, dibromohydantoin, trichloroisocyanuric acid and the like; the halogenation reagent L<NUM> is selected from phosphorus oxychloride, phosphorus oxybromide, thionyl chloride and the like; the basic reagent A is selected from sodium ethoxide, sodium methoxide, sodium hydride, potassium carbonate, cesium carbonate, the basic conditions can be further selected to be the above-defined basic reagent A; the sodium alkoxide is selected from sodium C<NUM>-C<NUM> alkoxide, such as sodium methoxide and sodium ethoxide.

In the above schemes, the ethyl p-toluenesulfonylglycinate raw material is prepared by the following method: p-toluenesulfonyl halide, ethyl glycinate or a salt thereof are dissolved in a solvent, and stirred while added pyridine dropwise until the reaction is completed. The salt of the ethyl glycinate is preferably ethyl glycinate hydrochloride, and the reaction solvent is preferably dichloromethane.

In the above schemes, in the reaction between methyl <NUM>-aminocrotonate and methyl propiolate, the molar ratio of the methyl <NUM>-aminocrotonate to the methyl propiolate is <NUM>:<NUM> to <NUM>:<NUM>, preferably <NUM>:(<NUM>-<NUM>); the reaction process includes: (<NUM>) methyl <NUM>-aminocrotonate, methyl propiolate, and a solvent are added, and reacted by heating for <NUM>-<NUM> hours, preferably <NUM> hours, wherein the reaction temperature is <NUM>- <NUM>; (<NUM>) after the reaction is completed, a basic reagent is added and the reaction is continued for <NUM>-<NUM> hours, preferably <NUM> hours, wherein the reaction temperature is <NUM>-<NUM>, the basic reagent is preferably sodium hydroxide, and the molar ratio of the basic reagent to methyl <NUM>-aminocrotonate is <NUM>:<NUM> to <NUM>:<NUM>, more preferably <NUM>:(<NUM>-<NUM>).

In the above schemes, in the reaction between the intermediate M8 and the halogenation reagent L<NUM>, the molar ratio of the halogenation reagent to the M8 is (<NUM>-<NUM>):<NUM>, preferably <NUM>-<NUM>:<NUM>, the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, and the reaction time is <NUM>-<NUM>, preferably <NUM>-<NUM>.

In the above schemes, in the reaction between the intermediate M3 or M9 and the halogenation reagent Li, an initiator such as azobisisobutyronitrile or benzoyl peroxide is preferably added, and the reaction solvent may be a halogenated hydrocarbon, preferably dichloromethane, chloroform, carbon tetrachloride; the molar ratio of M3 or M9: Li: initiator is <NUM>:(<NUM>-<NUM>):(<NUM>-<NUM>); preferably <NUM>:(<NUM>-<NUM>):(<NUM>-<NUM>); the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, and the reaction time is <NUM>-<NUM>, preferably <NUM>-<NUM>.

In the above schemes, in the reaction between the intermediate M4 or M10 and the ethyl p-toluenesulfonylglycinate, the molar ratio of the M4 or M10 to the ethyl p-toluenesulfonylglycinate is <NUM>:<NUM> to <NUM>:<NUM>, preferably <NUM>:<NUM>, the reaction solvent is an alcohol reagent, preferably methanol or ethanol; the reaction further includes the subsequent ring-closure reaction, the molar ratio of the basic reagent added in the ring-closure reaction to the M4 or M10 is (<NUM>-<NUM>):<NUM>, preferably (<NUM>-<NUM>):<NUM>, the basic reagent is preferably added in two batches, and the ring-closure reaction is preferably carried out at room temperature; the reaction further includes the following post-treatment: the reaction solution is adjusted to a pH of <NUM>-<NUM>, preferably <NUM>-<NUM>, and filtered, the filter cake is dissolved with water, and the pH is adjusted to about <NUM>-<NUM>, followed by suction filtration to obtain the product.

In the above schemes, in the reaction between the intermediate M12 and R<NUM>OH, the Pd catalyst is selected from palladium chloride, palladium acetate, triphenylphosphine palladium and the like, preferably palladium acetate; a basic reagent is further added to the reaction, and the basic reagent can be the basic reagent A defined above, and further preferably cesium carbonate; a phosphine ligand is further added in the reaction, and the phosphine ligand is selected from triphenylphosphine, <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisdiphenylphosphine, <NUM>-dicyclohexylphosphino-<NUM>,<NUM>,<NUM>-triisopropylbiphenyl and the like, preferably <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisdiphenylphosphine; the solvent for the reaction is preferably DMSO, acetonitrile, dimethylformamide, the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, more preferably <NUM>, and the reaction time is <NUM>-<NUM> hours, preferably <NUM>-<NUM> hours, more preferably <NUM>-<NUM> hours; the reaction further includes the following post-treatment: the reaction solution is poured into a water-organic solvent mixed solution (preferably a water-ethyl acetate mixed solution), stirred, and filtered, the filtrate is subjected to phase separation, the aqueous phase is extracted with an organic solvent, and the organic phases are combined and separated by column chromatography to obtain the product.

In the above schemes, in the reaction between the intermediate M1, M6, M12 or M14 with the halogenation reagent L<NUM> respectively, the reaction solvent is preferably DMSO, acetonitrile, dimethylformamide, more preferably acetonitrile; the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, more preferably <NUM>, and the reaction time is <NUM>-<NUM> hours, preferably <NUM>-<NUM> hours, more preferably <NUM> hours; the reaction process further includes the following post-treatment: the solvent is evaporated under reduced pressure, and the residue is dissolved with an organic solvent (preferably ethyl acetate), washed with water and separated by column chromatography to obtain the product.

In the above schemes, in the reaction between the intermediate M2, M7, M13 or M15 with glycine respectively, the reaction solvent is preferably DMSO, acetonitrile, dimethylformamide, more preferably DMSO; the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, more preferably <NUM>-<NUM>, and the reaction time is <NUM>-<NUM> hours, preferably <NUM>-<NUM> hours, more preferably <NUM> hours; the reaction process further includes the following post-treatment: the reaction solution is poured into water, and optionally washed with an organic solvent (preferably ethyl acetate), the pH of the aqueous phase is adjusted to <NUM>-<NUM>, preferably <NUM>-<NUM>, to precipitate out a solid, which is then dried to obtain the product.

Compound M15 is not according to the current invention and serves illustrative purposes only :
<CHM>
wherein, R<NUM>, R<NUM>, X are as defined above.

The preparation of the prodrug includes reacting a compound of formula I, formula II, formula III/formula IIIa, formula IV or formula V with an esterification reagent under basic conditions to obtain a compound of formula Ib, formula IIb, formula IIIb, Formula IVb, Formula Vb or Formula Vib (the reaction of formula I is not according to the current invention and serves illustrative purposes only). The scheme is further illustrated as follows:
<CHM>.

In the above scheme, the basic conditions can be as follows: the basic agent is selected from methylamine, ethylamine, diethylamine, triethylamine, diisopropylethylamine, imidazole, pyridine, <NUM>-methylpyridine, DMAP, DBU and the like, preferably triethylamine and diisopropylethylamine; the solvent in the reaction may include DMF, DMSO, acetonitrile; the molar ratio of the esterification reagent, the compound of formula I (formula II, formula III/formula IIIa, formula IV or formula V) and the basic reagent is <NUM>:(<NUM>-<NUM>):(<NUM>-<NUM>), preferably <NUM>:(<NUM>-<NUM>):(<NUM>-<NUM>); the reaction temperature is <NUM>-<NUM>, preferably <NUM>-<NUM>, more preferably <NUM>, and the reaction time is <NUM>-<NUM> hours, preferably <NUM>-<NUM> hours, more preferably <NUM> hours.

The reaction process further includes the following post-treatment: the reaction solution is poured into a mixture of water and organic solvent (preferably a mixture of water and ethyl acetate), and stirred, the aqueous phase is extracted with an organic solvent, and the organic phases are combined, concentrated under reduced pressure, and separated by column chromatography to obtain the product.

In certain embodiments, the esterification reaction is preferably:
<CHM>.

Wherein, Hal is halogen; the halogen can be selected from F, Cl, Br, I; the C<NUM>-C<NUM> alkyl (C=O)OCH<NUM>-Hal is further preferably C<NUM>-C<NUM> alkyl (C=O)OCH<NUM>- Hal, more preferably chloromethyl pivalate.

In some embodiments, the pharmaceutical composition of the present disclosure further comprises a therapeutically effective amount of the compound of the present disclosure or a tautomer, optical isomer, N-oxide, solvate, pharmaceutically acceptable salt or prodrug thereof and a pharmaceutically acceptable carrier.

The compound of the present disclosure and the pharmaceutical composition comprising it have HIF-PHD inhibitory activity, and can be used to protect from, treat or alleviate anemia, ischemia, angina, myocardial infarction, metabolic disorders or wound healing diseases in patients. The ischemia includes myocardial ischemia, the anemia includes anemia caused by acute or chronic kidney disease, infection, inflammation, cancer, radiation, toxins, diabetes or surgery. The infection includes AIDS infection.

The compound of the present disclosure and the pharmaceutical composition comprising it can also be used to treat or alleviate HIF-related and/or EPO-related diseases or conditions in patients, for example, to promote endogenous EPO production and to stabilize HIFα.

In some embodiments, the medicament is used to protect from, treat, or alleviate diseases mediated at least in part by HIF prolyl hydroxylase or the medicament is used to treat diseases that require inhibition of the effect of HIF-PHD.

In some embodiments, the medicament is used to protect from, treat, or alleviate anemia, ischemia, angina, myocardial infarction, metabolic disorders or wound healing diseases in patients. The ischemia includes myocardial ischemia, the anemia includes anemia caused by acute or chronic kidney disease, infection, inflammation, cancer, radiation, toxins, diabetes or surgery. The infection includes AIDS infection. Anemic conditions may further be related to procedures or treatments including, for example, radiation therapy, chemotherapy, dialysis, and surgery. In addition, anemia is related to abnormal hemoglobin and/or red blood cells, such as those found in microcytic anemia, hypochromic anemia, aplastic anemia and other disorders.

In some embodiments, the medicament is preferably used to treat renal anemia diseases or conditions.

In some embodiments, the medicament is used to treat or alleviate HIF-related and/or EPO-related diseases or conditions in patients, for example, to stabilize HIFα; for example, to promote endogenous EPO production. The individual is undergoing preventive or concurrent specific treatment or surgery, for example, an HIV-infected anemia patient being treated with azidothymidine (zidovudine) or other reverse transcription inhibitors, an anemia cancer patient receiving chemotherapy with or without cisplatin or an anemic or non-anemic patient who is planning to undergo surgery. In addition, the compound can be used to increase the endogenous EPO content of an anemic or non-anemic patient who is planning to undergo surgery, thereby reducing the need for allogeneic blood transfusion or promoting blood reserves before surgery.

In some embodiments, the medicament is a medicament that meets the needs to increase iron intake, iron utilization and the like.

The term "optional" or "optionally" means that the event or situation described later can but does not necessarily occur, and the description includes the situation in which the event or situation occurs and the situation in which it does not occur.

The term "alkyl" includes Ci-Ce alkyl, preferably C<NUM>-C<NUM> alkyl, which can be straight or branched, and further includes but is not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl. The term also includes the alkyl in all groups that involve alkyl, for example, alkoxy, halogen-substituted alkyl and the like.

The term "aromatic ring" means a monovalent group remained after removing a hydrogen atom from the carbon on the aromatic nucleus of an aromatic hydrocarbon molecule, including C<NUM>-C<NUM> aromatic ring, and further including but not limited to phenyl and naphthyl.

The term "aromatic heterocycle" or heteroaromatic ring means a monovalent group remained after removing a hydrogen atom from the carbon on the aromatic nucleus of a heteroaromatic compound molecule, wherein the heteroatom is selected from N, O or S, including <NUM>-<NUM> membered aromatic heterocycle. The aromatic heterocycle may be a monocyclic ring or a condensed ring, and may be partially unsaturated. The aromatic heterocycle also includes five- or six-membered nitrogen-containing aromatic heterocycle. The aromatic heterocycle includes but is not limited to pyridine, pyrazine, pyridazine, pyrrole, imidazole, thiophene, furan. The aromatic ring and aromatic heterocycle may be further substituted with a substituent.

The term "halogen" refers to fluorine (F), chlorine (Cl), bromine (Br) or iodine (I).

The term "substituted with one or more substituents" includes, but is not limited to, substitution by one, two, three or four substituents.

The compound of the present disclosure includes the compound or a tautomer, optical isomer, N-oxide, solvate, pharmaceutically acceptable salt or prodrug thereof; the compound further includes compounds represented by formula I, formula II, formula III, formula IIIa, formula IV, formula V, formula Ib, formula IIb, formula IIIb, formula IVb, formula Vb, and formula VIb.

The salt of the compound of the present disclosure preferably includes a pharmaceutically acceptable salt of the compound. The salt can be prepared by any suitable method provided in the literature, for example, with the use of an inorganic acid such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid and phosphoric acid; or with the use of an organic acid such as acetic acid, maleic acid, succinic acid, mandelic acid, fumaric acid, malonic acid, pyruvic acid, oxalic acid, glycolic acid and salicylic acid; pyranonic acids such as glucuronic acid and galacturonic acid; α-hydroxy acids, such as citric acid and tartaric acid; amino acids, such as aspartic acid and glutamic acid; aromatic acids, such as benzoic acid and cinnamic acid; sulfonic acids, such as p-toluenesulfonic acid, ethylsulfonic acid.

In the present disclosure, the solvate is a form of the compound of the present disclosure which, in a solid or liquid state, forms a complex by coordination with a solvent molecule. A hydrate is a specific form of solvate in which the coordination is carried out with water. In the present disclosure, the preferred solvate is a hydrate.

The term "prodrug" or "drug precursor" means a compound that converts into the compound represented by the afore-mentioned formula or the afore-mentioned specific compound in vivo. Such conversion is affected by the hydrolysis of the prodrug in the blood or the enzymatic conversion of the prodrug into the parent structure in the blood or tissue. The prodrug of the present disclosure can be an ester. In the existing invention, the esters that can be used as prodrugs include phenyl esters, aliphatic (C<NUM>-<NUM>) esters, acyloxymethyl esters, carbonates, carbamates, and amino acid esters. For example, a compound in the present disclosure contains hydroxyl/carboxyl, and then it can be acylated to obtain a compound in the form of a prodrug. Other prodrug forms include phosphate esters, for example, phosphate esters obtained by phosphorylation of the parent hydroxyl group.

In the present disclosure, the desired pharmacological effect can be achieved by administering a pharmaceutical composition to a patient in need thereof. For the purpose of the present disclosure, a patient is a mammal, including humans, in need of treatment for a specific condition or disease.

In the present disclosure, the pharmaceutically acceptable carrier may be a carrier that is relatively non-toxic and harmless to the patient at a concentration consistent with the effective activity of the active ingredient, so that any side effect caused by the carrier will not destroy the beneficial effect of the active ingredient. The pharmaceutically effective amount of the compound or a pharmaceutically acceptable salt thereof is preferably an amount that produces a result or effect on the specific condition being treated. Any effective conventional dosage unit form including immediate release, sustained release and timed release preparations can be used. The compound of the present disclosure can be administered together with a pharmaceutically acceptable carrier well known in the art in the following manner: oral, parenteral, local, nasal, eye, sublingual, rectal, vaginal administration, and the like.

For oral administration, the compound of the present disclosure or a pharmaceutically acceptable salt thereof can be formulated into solid or liquid preparations, such as capsules, pills, tablets, troche, lozenge, melt, powder, solution, suspension or emulsion, and can be prepared according to methods known in the art for preparing pharmaceutical compositions. The solid unit dosage form may be a capsule, which may be an ordinary hard capsule or soft capsule, containing, for example, a surfactant, a lubricant, and an inert filler (such as lactose, sucrose, calcium phosphate, and corn starch).

In the present disclosure, the compound of the present disclosure or a pharmaceutically acceptable salt thereof and a conventional tablet excipient(such as lactose, sucrose and corn starch) can also be combined with the following materials and compressed into tablets: binders (such as gum arabic, corn starch or gelatin), disintegrants (such as potato starch, alginic acid, corn starch and guar gum, tragacanth gum, gum arabic) used to assist the disintegration and dissolution of tablets after administration, lubricants (such as talc, stearic acid or magnesium stearate, calcium stearate or zinc stearate) used to improve the fluidity of tablet granulation and prevent the tablet material from adhering to the surface of the tablet die and punch, dyes, colorants and flavors (such as peppermint oil, wintergreen oil or cherry flavor) used to improve the organoleptic properties of tablets and make them more acceptable to patients. Suitable excipients for oral liquid dosage forms include dicalcium phosphate and diluents, for example, water and alcohols (such as ethanol, benzyl alcohol and polyvinyl alcohol), with or without the addition of pharmaceutically acceptable surfactants, suspension agents or emulsifiers. Various other substances may be present as coatings or to modify the physical form of the dosage unit. For example, tablets, pills or capsules can be coated with shellac, sugar or both. Dispersible powders and granules are suitable for the preparation of aqueous suspensions. They provide active ingredients mixed with dispersants or wetting agents, suspending agents, and one or more preservatives. Examples of suitable dispersants or wetting agents and suspending agents are those mentioned above. Additional excipients may also be present, such as those flavors and colorants described above.

The pharmaceutical composition of the present disclosure may also be in the form of an oil-in-water emulsion. The oil phase may be a vegetable oil, such as liquid paraffin or a mixture of vegetable oils. Suitable emulsifiers may be (<NUM>) natural gums, such as gum arabic and tragacanth gum, (<NUM>) natural phospholipids, such as soybean phospholipids and lecithin, and (<NUM>) esters or partial esters derived from fatty acids and hexitol anhydrides, such as sorbitan monooleate, (<NUM>) condensation products of the partial esters with ethylene oxide, such as polyoxyethylene sorbitan monooleate. The emulsion may also contain sweeteners and flavors. Oily suspensions can be formulated by suspending the active ingredient in vegetable oil (for example, peanut oil, olive oil, sesame oil or coconut oil) or in mineral oil (for example, liquid paraffin). The oily suspension may contain a thickening agent, such as beeswax, hard paraffin or cetyl alcohol. The suspension may also contain one or more preservatives, such as ethyl p-hydroxybenzoate or n-propyl p-hydroxybenzoate; one or more colorants; one or more flavors; and one or more sweeteners, such as sucrose or saccharin. Syrups and elixirs can be formulated with sweeteners (such as glycerol, propylene glycol, sorbitol or sucrose). Such preparations may also contain buffers and preservatives (such as methyl paraben and propyl paraben) as well as flavors and colorants.

The compound of the present disclosure can also be administered parenterally, that is, subcutaneously, intravenously, intraocularly, intrasynovially, intramuscularly or intraperitoneally, at the injection dose of the compound. The injection dose is preferably in a physiologically acceptable diluent containing a pharmaceutical carrier. The pharmaceutical carrier can be a sterile liquid or a mixture of liquids, the liquid is such as water, saline, glucose solution and related sugar solutions, alcohols such as ethanol, isopropanol or cetyl alcohol, glycols such as propylene glycol or polyethylene glycol, glycerol ketals such as <NUM>,<NUM>-dimethyl-<NUM>,<NUM>-dioxolane-<NUM>-methanol, ethers such as polyethylene glycol <NUM> (PEG400), oils, fatty acids, fatty acid esters or fatty acid glycerides or acetylated fatty acid glycerides, the diluent is the added with or without pharmaceutically acceptable surfactants, such as soap or detergent, suspending agents such as pectin, carbomer, methyl cellulose, hypromellose or carboxymethyl cellulose, or emulsifiers and other pharmaceutical adjuvants.

Exemplary oils that can be used in the parenteral preparations of the present disclosure are those derived from petroleum, animal, vegetable or synthetic sources, such as peanut oil, soybean oil, sesame oil, cottonseed oil, corn oil, olive oil, petrolatum and mineral oil. Suitable fatty acids include oleic acid, stearic acid, isostearic acid and myristic acid. Suitable fatty acid esters are, for example, ethyl oleate and isopropyl myristate. Suitable soaps include fatty acid alkali metal salts, ammonium salts and triethanolamine salts, and suitable detergents include cationic detergents such as dimethyl dialkylammonium halides, alkyl pyridinium halides and alkylamine acetates; anionic detergents such as alkyl sulfonates, aryl sulfonates and olefin sulfonates, alkyl sulfates and alkyl sulfosuccinates, olefin sulfates and olefin sulfosuccinates, ether sulfates and ether sulfosuccinates and monoglyceride sulfates and monoglyceride sulfosuccinates; non-ionic detergents, such as fatty amine oxides, fatty acid alkanolamides and poly(oxyethylene-oxypropylene), ethylene oxide copolymers or propylene oxide copolymers; and amphoteric detergents, such as alkyl-β-aminopropionates and <NUM>-alkylimidazoline quaternary ammonium salts, and mixtures thereof.

The parenteral composition of the present disclosure may generally comprise about <NUM>% to about <NUM>% by weight of the active ingredient in solution. Preservatives and buffers can also be used advantageously. In order to minimize or eliminate irritation to the injection site, such compositions may comprise a nonionic surfactant with a hydrophilic-lipophilic balance (HLB) of preferably about <NUM> to about <NUM>. The amount of surfactant in such preparations is preferably about <NUM>% to about <NUM>% by weight. The surfactant may be a single component having the above-mentioned HLB or a mixture of two or more components having the desired HLB. Exemplary surfactants for parenteral preparations are polyethylene sorbitan fatty acid esters, such as sorbitan monooleate, and a high molecular weight adduct of ethylene oxide and a hydrophobic matrix. The hydrophobic matrix is formed by the condensation of propylene oxide and propylene glycol.

The pharmaceutical composition may be in the form of a sterile aqueous suspension for injection. Such suspensions can be formulated according to known methods using the following materials: suitable dispersants or wetting agents and suspending agents, such as sodium carboxymethyl cellulose, methyl cellulose, hypromellose, sodium alginate, polyvinylpyrrolidone, tragacanth gum and gum arabic; dispersants or wetting agents, which can be natural phospholipids (such as lecithin), condensation products of alkylene oxides and fatty acids (such as polyoxyethylene stearate), condensation products of ethylene oxide and long-chain fatty alcohols (such as PEG-<NUM> cetanol), condensation products of ethylene oxide and partial esters derived from fatty acids and hexitol (such as polyoxyethylene sorbitol monooleate) or condensation products of ethylene oxide and partial esters derived from fatty acids and hexitol anhydride (such as polyoxyethylene sorbitan monooleate).

The sterile injection preparation may also be a sterile solution or suspension for injection in a non-toxic parenterally acceptable diluent or solvent. Usable diluents and solvents are, for example, water, Ringer's solution, isotonic sodium chloride solution, and isotonic glucose solution. In addition, sterile non-volatile oils are routinely used as solvents or suspension media. In this regard, any non-volatile oils with little irritation can be used, including synthetic monoglycerides or diglycerides. In addition, fatty acids (such as oleic acid) can be used in the preparation of injections.

The composition of the present disclosure can also be administered in the form of suppositories for rectal administration of drugs. The composition can be prepared by mixing the drug with a suitable non-irritating excipient that is solid at normal temperature but liquid at rectal temperature and can therefore melt in the rectum to release the drug. Such substance includes, for example, cocoa butter and polyethylene glycol.

Controlled release preparations for parenteral administration include liposomal microspheres, polymer microspheres and polymer gel preparations known in the art.

It may be required or necessary to deliver the pharmaceutical composition to the patient via a mechanical delivery device. The construction and use of the mechanical delivery device for delivering the medicament are well known in the art. For example, a direct technique for administering a drug directly to the brain often involves placing a drug delivery catheter into the patient's ventricular system to bypass the blood-brain barrier.

The compound of the present disclosure can be administered as a single agent or in combination with one or more other agents, wherein the combination does not cause unacceptable adverse reactions. Suitable active agents in the combination include: ACE inhibitors, angiotensin II receptor antagonists, β-receptor blockers, calcium antagonists, PDE inhibitors, mineralocorticoid receptor antagonists, diuretics, aspirin, iron supplements, vitamin B12 and folic acid supplements, statins, digitalis derivatives (digoxin), tumor chemotherapy drugs and antibiotics.

The term "erythropoietin (EPO)-related diseases" refers to any condition associated with lower than normal, abnormal or improper regulation of endogenous erythropoietin. EPO-related diseases include any condition for which an increase in EPO levels will bring beneficial therapeutic effect. EPO is a naturally occurring hormone produced with HIFα, which stimulates the production of red blood cells that carry oxygen throughout the body. EPO-related diseases include, but are not limited to, anemia, including anemia related to diabetes, ulcers, renal failure, cancer, infection, dialysis, surgery and chemotherapy; conditions of ischemia and hypoxia, such as arterial occlusive disease, angina, intestinal infarction, pulmonary infarction, cerebral ischemia, and myocardial infarction.

The term "HIF-related diseases" refers to any condition associated with lower than normal, abnormal or improper regulation of HIF. HIF-related diseases include any condition for which an increase in HIF levels will bring beneficial therapeutic effect. HIF-related diseases include, but are not limited to, heart disease, stroke, peripheral vascular disease, ulcers, burns, chronic wounds, chronic ischemia, pulmonary embolism, ischemia-reperfusion injury, inflammation, and anemia.

HIF-related and/or EPO-related diseases include, but are not limited to, anemia, ischemia, vascular disease, angina, myocardial ischemia, myocardial infarction, metabolic disorders or wound healing.

The term "diseases mediated at least in part by HIF prolyl hydroxylase (HIF-PHD)", which can be used interchangeably with the term "HIF prolyl hydroxylase-related diseases", refers to any condition caused by abnormal HIF-PHD, including HIF-related diseases caused by abnormal HIF-PHD. HIF-PHD-related diseases include, but are not limited to, anemia and ischemia.

The term "anemia" refers to any abnormality or deficiency of hemoglobin or red blood cells that results in a decrease in oxygen content in the blood. It can be caused by various conditions, such as acute or chronic kidney disease, infection, inflammation, cancer, radiation, toxins, diabetes and surgery. The infection may be caused by, for example, viruses, bacteria and/or parasites. Inflammation may be caused by infection or autoimmune conditions such as rheumatoid arthritis. Anemia may also be related to blood loss caused by, for example, gastric ulcer, duodenal ulcer, hemorrhoids, gastric cancer or colorectal cancer, trauma, injury, surgical procedures and the like. The formation of anemia may also be related to radiotherapy, chemotherapy and renal dialysis. Anemia is also associated with HIV-infected patients receiving treatment with azidothymidine (zidovudine) or other reverse transcription inhibitors, and can develop in cancer patients receiving chemotherapy (e.g., chemotherapy with or without cisplatin). Aplastic anemia and myelodysplastic syndromes are diseases related to bone marrow failure that leads to reduced red blood cell production. In addition, anemia can be caused by defects or abnormalities in hemoglobin or red blood cells, for example, those found in microcytic anemia, hypochromic anemia and other disorders. Anemia can be caused by obstacles in iron transport, processing and utilization, for example, sideroblastic anemia.

The preparation method of the present disclosure will be further described in detail below in conjunction with specific examples. It should be understood that the following examples are only illustrative to illustrate and explain the present disclosure, and should not be construed as limiting the protection scope of the present disclosure. All technologies implemented based on the foregoing contents of the present disclosure are covered by the scope of the present disclosure. In the following examples, unless otherwise specified, all temperatures are in degrees Celsius. Unless otherwise specified, the raw material compounds are synthesized by the methods described herein or are commercially available, and purchased from the following manufacturers: J&K Chemicals, Beijing InnoChem Science & Technology Co. , Aladdin Bio-Chem, Alfa Aesar, Accela ChemBio Co. and the like.

In <NUM> of a reaction flask, p-toluenesulfonyl chloride (<NUM>, <NUM>. 0mol), glycine ethyl ester hydrochloride (<NUM>, <NUM>. 02mol), and dichloromethane (<NUM>) were added, stirred at room temperature, then pyridine (<NUM>, <NUM> mol) was added dropwise, thereafter, the reaction solution was reacted with stirring at room temperature for <NUM>. Purified water was added to the reaction flask, and an organic phase was separated. The organic phase was concentrated under reduced pressure to obtain a solid. The solid was dried under vacuum till constant weight, to obtain ethyl <NUM>-(<NUM>-methylphenylsulfonylamino) acetate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, methyl <NUM>-aminocrotonate (<NUM>, <NUM> mol), methyl propiolate (<NUM>, <NUM> mol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. To the reaction solution sodium hydroxide (<NUM>, <NUM> mol) was added, and the reaction was continued at <NUM> for <NUM>. The reaction solution was cooled, and poured slowly into <NUM> 1N of hydrochloric acid, to precipitate out a large amount of yellow solid. The reaction solution was adjusted to neutral with sodium carbonate, stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain methyl <NUM>-hydroxy-<NUM>-methylnicotinate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, methyl <NUM>-hydroxy-<NUM>-methylnicotinate (<NUM>, <NUM> mol), and phosphorus oxychloride (<NUM>) were added in sequence, heated to <NUM> and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and the residue was poured slowly into <NUM> of ice water, to precipitate out a large amount of gray-black solid. The system was stirred for <NUM>, and subjected to suction filtration. The filter cake was dried at room temperature to obtain methyl <NUM>-methyl-<NUM>-chloronicotinate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, methyl <NUM>-methyl-<NUM>-chloronicotinate (<NUM>, <NUM> mol), N-bromosuccinimide (<NUM>, <NUM> mol), benzoyl peroxide (<NUM>, <NUM> mol), and carbon tetrachloride (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and <NUM> of petroleum ether was added to the residue, to precipitate out a light yellow solid. The system was stirred for <NUM>, and subjected to suction filtration. The filter cake was dried under vacuum till constant weight, to obtain methyl <NUM>-bromomethyl-<NUM>-chloronicotinate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, methyl <NUM>-bromomethyl-<NUM>-chloronicotinate (<NUM>, <NUM> mol), ethyl <NUM>-(<NUM>-methylphenylsulfonylamino) acetate (<NUM>, <NUM> mol), and absolute ethanol (<NUM>) were added, stirred at room temperature, then sodium ethoxide (<NUM>, <NUM> mol) was added slowly, thereafter, the reaction solution was reacted with stirring at room temperature for <NUM>. The reaction solution was adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, filtered, and the filter cake was washed with purified water, and subjected to suction filtration, to obtain a yellow solid ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

<NUM>H NMR (<NUM>, DMSO-d<NUM>) δ: <NUM>-<NUM>(t, <NUM>), <NUM>-<NUM>(m, <NUM>), <NUM>-<NUM>(d, J=<NUM>, <NUM>), <NUM>-<NUM>(d, J=<NUM>, <NUM>), <NUM>(s, <NUM>), <NUM>(s, <NUM>).

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), phenol (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, the residue was separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain an off-white solid ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of solid. The system was stirred for <NUM>, and subjected to suction filtration. The filter cake was washed with purified water, and dried under vacuum till constant weight, to obtain an off-white solid <NUM>-(<NUM>-phenoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), p-hydroxyanisole (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and the residue was separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain a solid ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, to precipitate out a yellow solid. The system was adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, stirred for <NUM>, subjected to suction filtration, and dried under vacuum for <NUM>, to obtain an off-white solid2-(<NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), <NUM>-hydroxypyridine (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filter cake was washed with ethyl acetate, the filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-(pyrid-<NUM>-yloxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(pyrid-<NUM>-yloxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and the residue was separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain a white solid ethyl <NUM>-(pyrid-<NUM>-yloxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(pyrid-<NUM>-yloxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, to precipitate out a solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain a light yellow solid <NUM>-(<NUM>-(pyrid-<NUM>-yloxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-bromosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and the residue was separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain an off-white solid ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-phenoxy-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, to precipitate out a large amount of solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain an off-white solid <NUM>-(<NUM>-phenoxy-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was concentrated under reduced pressure to precipitate out a large amount of solid, followed by filtration to obtain a white solid ethyl <NUM>,<NUM>-dichloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>,<NUM>-dichloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>,<NUM>-dichloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), <NUM>-chlorophenol (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, concentrated under reduced pressure until a large amount of white solid was precipitated out, and the concentration was stopped. The reaction solution was cooled to precipitate for <NUM>, and subjected to suction filtration, to obtain a solid ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of white solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-bromosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, concentrated under reduced pressure until a large amount of white solid was precipitated out, and the concentration was stopped, The reaction solution was cooled to precipitate for <NUM>, and subjected to suction filtration, to obtain a solid ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of white solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-formamido), acetic acid <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, to precipitate out a large amount of solid. The system was stirred to precipitate for <NUM>, and subjected to suction filtration, to obtain a white solid ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-bromosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, and concentrated under reduced pressure until a large amount of solid was precipitated out, and the concentration was stopped. The system was stirred to precipitate for <NUM>, and subjected to suction filtration, to obtain a yellow solid ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of white solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, to precipitate out a large amount of solid. The system was stirred to precipitate for <NUM>, and subjected to suction filtration, to obtain a yellow solid ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-bromosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, to precipitate out a large amount of solid. The system was stirred to precipitate for <NUM>, and subjected to suction filtration, to obtain a white solid ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of white solid. The system was stirred for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid (<NUM>, <NUM>%).

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 79mmol), <NUM>-fluorophenol (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, and concentrated under reduced pressure, until a large amount of solid was precipitated out, and the concentration was stopped. The system was allowed to precipitate under refrigerated conditions overnight, and subjected to suction filtration, to obtain a white solid ethyl <NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM> %.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, to precipitate out solid. The system was stirred at room temperature for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid (<NUM>, <NUM>%).

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 79mmol), <NUM>-fluorophenol (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-(<NUM>-chlorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM>%.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), N-bromosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, directly separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain a white solid ethyl <NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM> %.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, to precipitate out solid. The system was stirred at room temperature for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-fluorophenoxy)-<NUM>-hydroxy-<NUM>-bromo-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid (<NUM>, <NUM>%).

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), p-hydroxyanisole (<NUM>, <NUM> mmol), palladium acetate (<NUM>, <NUM> mmol), <NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-bisphenyl phosphine (<NUM>, <NUM> mmol), cesium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into a mixed solution of <NUM> purified water and <NUM> ethyl acetate, stirred and filtered. The filtrate was subjected to phase separation, and the aqueous phase was further extracted once with <NUM> ethyl acetate. The ethyl acetate layers were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate /Vdichloromethane = <NUM>/<NUM>/<NUM>-<NUM>/<NUM>/<NUM>, and concentrated to obtain ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM> %.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 59mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, the residue was separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>-<NUM>/<NUM>, and concentrated to obtain a solid ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM> %.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-methoxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 53mmol) and dichloromethane (<NUM>) were added, and, under the protection of nitrogen, cooled to -<NUM>. Boron tribromide (<NUM>, <NUM>. 13mmol) was added, and further stirred for <NUM>. The reaction solution was heated to room temperature, and the reaction was continued for <NUM>. Ice was added to the reaction solution slowly for quenching. The system was stirred for <NUM>, adjusted with sodium hydroxide to neutral pH, and extracted twice with <NUM> ethyl acetate. The organic phases were combined, separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>, and concentrated to obtain a solid ethyl <NUM>-(<NUM>-hydroxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM> %.

In <NUM> of a reaction flask, ethyl <NUM>-(<NUM>-hydroxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, to precipitate out solid. The system was stirred at room temperature for <NUM>, and subjected to suction filtration. The obtained solid was dried under vacuum till constant weight, to obtain <NUM>-(<NUM>-(<NUM>-hydroxyphenoxy)-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid (<NUM>, <NUM>% ).

In <NUM> of a reaction flask, ethyl <NUM>-chloro-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 98mmol), sodium ethoxide ethanol solution (<NUM>, <NUM>. 99mmol), and absolute ethanol (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and then <NUM> of purified water was added to the residue, followed by adjusting with concentrated hydrochloric acid to a pH of <NUM>. The system was stirred for <NUM>, and filtered to obtain a solid ethyl <NUM>-ethoxy-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>%).

In <NUM> of a reaction flask, ethyl <NUM>-ethoxy-<NUM>-hydroxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 37mmol), N-chlorosuccinimide (<NUM>, <NUM> mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was concentrated under reduced pressure, and the residue was separated by column chromatography, eluted with V petroleum ether/V ethyl acetate = <NUM>/<NUM>-<NUM>/<NUM>, and concentrated to obtain a solid ethyl <NUM>-ethoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate, <NUM>, <NUM> %.

In <NUM> of a reaction flask, ethyl <NUM>-ethoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM> mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled, poured into <NUM> purified water, adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, to precipitate out solid, and then filtered. The obtained solid was dried under vacuum till constant weight, to obtain a pink solid
<NUM>-(<NUM>-ethoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid (<NUM>, <NUM>%).

In <NUM> of a reaction flask, <NUM>-(<NUM>-phenoxy-<NUM>-hydroxy-<NUM>-chloro-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid (<NUM>, <NUM>. 35mmol), chloromethyl pivalate (<NUM>, <NUM> mmol), diisopropylethylamine (<NUM>, <NUM> mmol), and N,N-dimethyl formamide (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was poured into <NUM> of a mixed solution of purified water and ethyl acetate. The system was stirred for <NUM>, and set aside for phase separation. The aqueous phase was extracted with ethyl acetate, and the organic phases were combined, and concentrated under reduced pressure. The residue was purified by column chromatography (petroleum ether - ethyl acetate = <NUM>-<NUM>), and the least polar component was collected, and concentrated under reduced pressure to obtain a white solid (<NUM>, <NUM>%).

Specific physical characterization results:.

In <NUM> of a reaction flask, methyl <NUM>-hydroxy-<NUM>-phenoxy-isoquinoline-<NUM>- carboxylate (<NUM>, <NUM>. 93mmol), N-chlorosuccinimide (<NUM>, <NUM>. 78mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled to room temperature, to precipitate out a large amount of solid. The system was stirred at room temperature for <NUM>, and subjected to suction filtration. The filter cake was washed with acetonitrile, and dried under vacuum till constant weight <NUM>.

In <NUM> of a reaction flask, methyl <NUM>-chloro-<NUM>-hydroxy-<NUM>-phenoxy-isoquinoline-<NUM>- carboxylate (<NUM>, <NUM> mmol), glycine (<NUM>, <NUM>. 30mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, and extracted with ethyl acetate (<NUM>×<NUM>). The aqueous phase was adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, and extracted with ethyl acetate (<NUM>×<NUM>), and the organic phases were combined. The organic phase was washed with water, saturated brine, dried with anhydrous sodium sulfate, and subjected to suction filtration. The filtrate was concentrated under reduced pressure, to obtain an off-white solid, <NUM>.

In <NUM> of a reaction flask, ethyl <NUM>-hydroxy-<NUM>-phenoxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (<NUM>, <NUM>. 225mmol), glycine (<NUM> g, <NUM>. 674mmol), potassium carbonate (<NUM>, <NUM>. 674mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of solid. The system was stirred for <NUM>, and subjected to suction filtration. The filter cake was washed with purified water, and dried under vacuum till constant weight, to obtain an off-white solid <NUM>-(<NUM>-hydroxy-<NUM>-phenoxy-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>.

In <NUM> of a reaction flask, methyl <NUM>-hydroxy-<NUM>-phenoxy-isoquinoline-<NUM>-carboxylate (<NUM>, <NUM>. 86mmol), N-bromosuccinimide (<NUM>, <NUM>. 71mmol), and acetonitrile (<NUM>) were added, heated to <NUM>, and reacted for <NUM>. The reaction solution was cooled to room temperature, to precipitate out a large amount of solid. The system was stirred at room temperature for <NUM>, and subjected to suction filtration. The filter cake was washed with acetonitrile, and dried under vacuum till constant weight, <NUM>.

In <NUM> of a reaction flask, methyl <NUM>-bromo-<NUM>-hydroxy-<NUM>-phenoxy-isoquinoline-<NUM>-carboxylate (<NUM>, <NUM>. 97mmol), glycine (<NUM>, <NUM>. 92mmol), potassium carbonate (<NUM>, <NUM> mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, extracted with ethyl acetate (<NUM>×<NUM>). The aqueous phase was adjusted with concentrated hydrochloric acid to a pH of <NUM>~<NUM>, and extracted with ethyl acetate (100mlx2), and the organic phases were combined. The organic phase was washed with water, saturated brine, dried with anhydrous sodium sulfate, and subjected to suction filtration. The filtrate was concentrated under reduced pressure, to obtain an off-white solid, <NUM>.

In <NUM> of a reaction flask, methyl <NUM>-hydroxy-<NUM>-methyl-<NUM>-phenoxy-<NUM>,<NUM>-naphthyridine-<NUM>-carboxylate (prepared according to the method of Example <NUM> in <CIT>) (<NUM>, <NUM> mmol), glycine (<NUM> g, <NUM>. 8mmol), potassium carbonate (<NUM>, <NUM>. 8mmol), and dimethyl sulfoxide (<NUM>) were added, heated to <NUM> and reacted for <NUM>. The reaction solution was poured into <NUM> purified water, adjusted with concentrated hydrochloric acid to a pH of <NUM>-<NUM>, to precipitate out a large amount of solid. The system was stirred for <NUM>, and subjected to suction filtration. The filter cake was washed with purified water, and dried under vacuum till constant weight, to obtain a light yellow solid <NUM>-(<NUM>-hydroxy-<NUM>-methyl-<NUM>-phenoxy-<NUM>,<NUM>-naphthyridine-<NUM>-formamido) acetic acid, <NUM>.

A test compound was dissolved in dimethyl sulfoxide into a <NUM> stock solution, and then was diluted with <NUM>% FBS-containing DMEM medium into <NUM> and <NUM> for later use. Human liver cancer cell Hep3B cells were seeded in a <NUM>-well plate with a density of <NUM>*<NUM><NUM> cells/well. The cells were adherent cultured overnight, and after discarding the used medium in the <NUM>-well culture plate, the cells were washed once with <NUM>% FBS-containing DMEM medium. Each <NUM>µl of the test compound at concentrations of <NUM> and <NUM> was added to the well, with <NUM> duplicate wells for each concentration. <NUM>% FBS-containing DMEM medium was used instead of the drug solution as the control well. After incubation in a <NUM>, <NUM>% CO<NUM> incubator for <NUM>, the supernatant was taken as a sample and frozen at -<NUM> for later use. An Elisa kit (abcam) was used to detect EPO in the cell supernatant. A microplate reader was used to detect the OD value at <NUM>/<NUM>. The results were as follows:.

The biological activity results showed that the compounds of the present disclosure had an EPO-enhancing effect, at least not less than that of the positive control drug FG4592. Preferably, Link-<NUM>, Link-<NUM>, Link-<NUM> and Link-<NUM> had more significant EPO-enhancing effect, with the expression of EPO in cells higher than that of the positive control drug FG4592.

The results showed that the compounds of the present disclosure could all promote the expression of erythropoietin in vivo. Among them, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, and Link-<NUM> had higher activity, and they could significantly promote the expression of erythropoietin at <NUM>/kg, with the EPO-enhancing effect all higher than that of the control samples BAY85-<NUM> (<NUM>/kg) and FG4592 (<NUM>/kg).

A represents <NUM><EPO OD value<<NUM>, B represents <NUM><EPO OD value<<NUM>, C represents <NUM><EPO OD value<<NUM>, and D represents EPO OD value><NUM>.

(<NUM>) <NUM> c57 mice, male, were divided into <NUM> groups, <NUM> mice in each treatment group. The mice in the treatment groups were orally administered once with Link-<NUM> and Link-<NUM>, products prepared according to Comparative Examples <NUM>, <NUM>, <NUM>, and <NUM> (denoted as compounds of Comparative Examples <NUM>-<NUM>) (<NUM>/kg). <NUM> hours after the administration, blood was taken, and plasma was collected for EPO detection with an ELISA kit (R&D Co.

In order to compare the erythropoietin expression effect of the compounds of the present disclosure with that of the compounds of Comparative Examples <NUM>-<NUM>, the EPO ratios of compounds Link118 and Link121 of the present disclosure relative to compounds of Comparative Examples <NUM>-<NUM> were recorded respectively. The results showed that the compounds of the present disclosure could significantly promote the expression of EPO, and their EPO-enhancing effect was significantly higher than that of the compounds of Comparative Examples <NUM>-<NUM>.

<NUM> Balb/c mice, male, were divided into <NUM> groups, <NUM> mice in each treatment group. In the positive drug control groups: the mice in the FG-<NUM> treatment groups were orally administered once, at two doses of <NUM>/kg and <NUM>/kg, and the mice in the rhEPO treatment group was intraperitoneally injected once, at a dose of <NUM> IU/kg. The compounds of the present disclosure were all orally administered once at a dose of <NUM>/kg. <NUM> after the administration, blood was collected from the orbit of all animals, and subjected to EDTA-K2 anticoagulation. Then reticulocytes (RETIC) were counted with an automatic blood cell analyzer. The results showed that, the mice in the FG4592 group of at a dose of <NUM>/kg had no significant difference from normal animals, while the mice treated with other control compounds and the compounds of the present disclosure all had higher reticulocyte counts than that of normal animals (p<<NUM>), with the effect of some compounds better than that of small molecule positive control drug and rhEPO.

A test compound was dissolved in dimethyl sulfoxide into a <NUM> stock solution, and then was diluted with <NUM>% FBS-containing DMEM medium into <NUM>, <NUM> and <NUM> for later use. Human liver cancer cells Hep3B were seeded in a six-well plate at a density of <NUM>*<NUM><NUM> cells/well, <NUM> per well. After cultivation overnight, the cells were treated with compounds at different concentrations for <NUM>. The proteins were extracted for western blot and further grayscale analysis. The results were as follows:.

The protein level results showed that as compared with the blank control, the HIF-1α and HIF-2α protein expression in the cells treated with Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, and Link-<NUM> was all higher than that of the blank control, and all these compounds could promote the expression of HIF-1α and HIF-2α; and the promoting effect on HIF-1α expression of Link-<NUM> was stronger than that of the positive control drug FG4592.

The compounds of the present disclosure were subjected to the CYP450 enzyme inhibition assay. The experimental results showed that the compounds of the present disclosure had low inhibitory activity against CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4-M enzymes, and high safety.

Whole-cell patch clamp technique was used to record hERG current. A cell suspension was added to a <NUM> Petri dish, and the dish was then placed on an inverted microscope stage. After the adherence of cells, they were perfused with extracellular fluid at a flow rate of <NUM>-<NUM>/min. A glass microelectrode was drawn by a microelectrode puller in two steps, and the pipette tip resistance was between <NUM>-<NUM> MΩ. After establishing the whole cell recording, the clamp potential was held at -<NUM> mV, followed by depolarization to +<NUM> mV when given voltage stimulation and then repolarization to -<NUM> mV to elicit hERG tail current. All recordings were performed after the current was stable. Extracellular perfusion administration started from a low concentration, staying for <NUM>-<NUM> at each concentration until the current was stable, and then cells were further perfused with the next concentration. In this experiment, Amitriptyline was used as a positive control. The inhibition of each compound on hERG was as follows.

The results of this study showed that the inhibitory effect of Link-<NUM><NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM>, Link-<NUM> and Link-<NUM> on hERG current at the highest test concentration (<NUM>) was far from the IC<NUM> value, indicating that the compounds of the present disclosure had no obvious inhibitory effect on hERG channels. The results of this study could be part of a comprehensive cardiac safety assessment.

IC<NUM> values of the compounds on Herg current recorded on CHO-K1 stable cell line.

<NUM> SD rats were subjected to residual kidney surgery after anesthesia (left kidney was resected, one third of the right kidney was left, and the resected kidney part was weighed to confirm the surgical error). After <NUM> weeks, <NUM> surviving rats were subjected to blood cell dection and then assigned according to the HCT value. <NUM> rats in good condition were selected and divided into the following groups: Link-<NUM> (<NUM>, <NUM>/kg), Link-<NUM> (<NUM>, <NUM>/kg), and FG-<NUM> (<NUM>/kg), <NUM> rats in each treatment group, and <NUM> in the model group. <NUM> rats were assigned to the blank control group. The rats were administered three times each week (administered on Monday, Wednesday, and Friday), for <NUM> times, and blood was taken <NUM> hours after the last administration (tested by blood routine, blood biochemistry, hepcidin kit).

Conclusion: as compared with the blank control group, the red blood cell (RBC), hemoglobin (HGB), and hematocrit (HCT) of the rats in the model group were significantly decreased, indicating that the model was successfully established. As compared with the model group, Link-<NUM> and FG-<NUM> both could significantly increase RBC, HGB, and HCT in rats with residual kidney, the efficacy of Link-<NUM> was better than that of FG-<NUM> at the same dose, and Link-<NUM> could significantly increase HGB and HCT in rats with residual kidney; as compared with the model group, Link-<NUM><NUM> and FG-<NUM> could significantly inhibit hepcidin in rats with residual kidney, and Link-<NUM> reduced hepcidin in rats; as compared with the blank control group, Link-<NUM>, Link-<NUM>, FG-<NUM> had no significant effect on liver glutamic-pyruvic aminotransferase and glutamic-oxalacetic transaminase.

VHL/elongin B/elongin C were constructed, expressed and purified, and VHL was labeled. PHD1, PHD2 and PHD3 were constructed, expressed and purified. VBC protein was labeled with DELFIA Eu-Labeling Kit. A NeutrAvidin <NUM>-well plate was blocked after the addition of <NUM>µL Blocker Casein to each well, followed by incubation for <NUM>. Each well was washed <NUM> times by adding <NUM>µL of washing buffer each time. A <NUM> HIF-1α <NUM>-<NUM> solution was prepared with washing buffer, and <NUM>µL of the solution was added to each well, followed by incubation for <NUM>. Each well was washed <NUM> times by adding <NUM>µL of washing buffer each time. A <NUM> Biotin solution was prepared with Blocker Casein, and <NUM>µL of the solution was added to each well, followed by incubation for <NUM>. Each well was washed <NUM> times by adding <NUM>µL of washing buffer each time. A <NUM>× compound solution was prepared with PHD reaction buffer, with the final concentration of DMSO being <NUM>%. PHD solutions were prepared with PHD reaction buffer, and the concentrations of PHD1, <NUM>, and <NUM> solutions were <NUM> ng/µL, <NUM> ng/µL, and <NUM> ng/µL, respectively. <NUM>µL of the PHD solution was added to each compound well, followed by the addition of <NUM>µL of the compound solution; <NUM>µL of the PHD solution was added to each full active well, followed by the addition of <NUM>µL of the PHD reaction buffer; and <NUM>µL of the PHD reaction buffer was added to each blank well. After mixing homogeneously, the wells were incubated for <NUM>. Each well was washed <NUM> times by adding <NUM>µL of washing buffer each time. A <NUM> ng/µL Eu-VBC solution was prepared with Eu-VBC binding buffer, and <NUM>µL of the solution was added to each well, followed by incubation for <NUM>. Each well was washed <NUM> times by adding <NUM>µL DELFIA Wash Concentrate each time. <NUM>µL DELFIA Enhancement Solution was added to each well. A microplate reader was used to read TR-Fluorescence at Ex340 and Em615. The flurescence of the sample wells was recorded as FLUsample, the flurescence of the full active wells was recorded as FLU100%, and the flurescence of the blank well was recorded as FLU0%.

The inhibition rate was calculated according to the following formula:
Inhibition rate = (FLU100%-FLUsample) / (FLU100%-FLU0%) × <NUM>%.

The experimental results showed that Link-<NUM><NUM> and Link-<NUM> had better effect on PHD1, PHD2 and PHD3 than those of compounds of Comparative Examples <NUM>-<NUM>.

The embodiments of the present disclosure have been described above. However, the present disclosure is not limited to the above-mentioned embodiments.

Claim 1:
A compound represented by formula (II) or a tautomer, optical isomer, N-oxide, solvate, pharmaceutically acceptable salt thereof:
<CHM>
wherein,
R<NUM> is selected from H or Ci-Ce alkyl;
R<NUM> is selected from H, halogen, Ci-Ce alkyl or Z-R<NUM>;
n is selected from <NUM>-<NUM>;
Z is selected from O or S;
R<NUM> is selected from C<NUM>-C<NUM> aromatic ring, <NUM>-<NUM> membered aromatic heterocycle, unsubstituted or optionally substituted with one or more substituents; the substituents are independently selected from OH, halogen, Ci-Ce alkyl, Ci-Ce alkoxy, halogen-substituted Ci-Ce alkyl, or R<NUM> is selected from H or Ci-Ce alkyl;
X is selected from halogen.