| Substance | Relationship Strength | Studies | Trials | Classes | Roles |
|---|
octane
Octanes: Eight-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives.. octane : A straight chain alkane composed of 8 carbon atoms. | 1.98 | 1 | 0 | alkane | xenobiotic |
hydrogen carbonate
Bicarbonates: Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the pH of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity.. hydrogencarbonate : The carbon oxoanion resulting from the removal of a proton from carbonic acid. | 2 | 1 | 0 | carbon oxoanion | cofactor;
Escherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite |
histamine
[no description available] | 2.01 | 1 | 0 | aralkylamino compound;
imidazoles | human metabolite;
mouse metabolite;
neurotransmitter |
oxalic acid
Oxalic Acid: A strong dicarboxylic acid occurring in many plants and vegetables. It is produced in the body by metabolism of glyoxylic acid or ascorbic acid. It is not metabolized but excreted in the urine. It is used as an analytical reagent and general reducing agent.. oxalic acid : An alpha,omega-dicarboxylic acid that is ethane substituted by carboxyl groups at positions 1 and 2. | 3.06 | 1 | 0 | alpha,omega-dicarboxylic acid | algal metabolite;
human metabolite;
plant metabolite |
2,2'-dipyridyl
2,2'-Dipyridyl: A reagent used for the determination of iron.. 2,2'-bipyridine : A bipyridine in which the two pyridine moieties are linked by a bond between positions C-2 and C-2'. | 2.13 | 1 | 0 | bipyridine | chelator;
ferroptosis inhibitor |
cetyltrimethylammonium ion
Cetrimonium: Cetyltrimethylammonium compound whose salts and derivatives are used primarily as topical antiseptics.. cetyltrimethylammonium ion : A quaternary ammonium ion in which the substituents on nitrogen are one hexadecyl and three methyl groups. | 1.98 | 1 | 0 | quaternary ammonium ion | |
chlorpheniramine
Chlorpheniramine: A histamine H1 antagonist used in allergic reactions, hay fever, rhinitis, urticaria, and asthma. It has also been used in veterinary applications. One of the most widely used of the classical antihistaminics, it generally causes less drowsiness and sedation than PROMETHAZINE.. chlorphenamine : A tertiary amino compound that is propylamine which is substituted at position 3 by a pyridin-2-yl group and a p-chlorophenyl group and in which the hydrogens attached to the nitrogen are replaced by methyl groups. A histamine H1 antagonist, it is used to relieve the symptoms of hay fever, rhinitis, urticaria, and asthma. | 2.05 | 1 | 0 | monochlorobenzenes;
pyridines;
tertiary amino compound | anti-allergic agent;
antidepressant;
antipruritic drug;
H1-receptor antagonist;
histamine antagonist;
serotonin uptake inhibitor |
erythrosine
Fluoresceins: A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays. | 3.06 | 1 | 0 | | |
loratadine
Loratadine: A second-generation histamine H1 receptor antagonist used in the treatment of allergic rhinitis and urticaria. Unlike most classical antihistamines (HISTAMINE H1 ANTAGONISTS) it lacks central nervous system depressing effects such as drowsiness.. loratadine : A benzocycloheptapyridine that is 6,11-dihydro-5H-benzo[5,6]cyclohepta[1,2-b]pyridine substituted by a chloro group at position 8 and a 1-(ethoxycarbonyl)piperidin-4-ylidene group at position 11. It is a H1-receptor antagonist commonly employed in the treatment of allergic disorders. | 2.44 | 2 | 0 | benzocycloheptapyridine;
ethyl ester;
N-acylpiperidine;
organochlorine compound;
tertiary carboxamide | anti-allergic agent;
cholinergic antagonist;
geroprotector;
H1-receptor antagonist |
pheniramine
Pheniramine: One of the HISTAMINE H1 ANTAGONISTS with little sedative action. It is used in treatment of hay fever, rhinitis, allergic dermatoses, and pruritus. | 2.05 | 1 | 0 | pyridines;
tertiary amino compound | |
estriol
hormonin: estrogen replacement; each tablet contains 600 ug micronized 17beta-estradiol, 270 ug estriol and 1.4 mg estrone. chlorapatite : A phosphate mineral with the formula Ca5(PO4)3Cl. | 1.97 | 1 | 0 | 16alpha-hydroxy steroid;
17beta-hydroxy steroid;
3-hydroxy steroid | estrogen;
human metabolite;
human xenobiotic metabolite;
mouse metabolite |
thyroxine
Thyroxine: The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (MONOIODOTYROSINE) and the coupling of iodotyrosines (DIIODOTYROSINE) in the THYROGLOBULIN. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form TRIIODOTHYRONINE which exerts a broad spectrum of stimulatory effects on cell metabolism.. thyroxine : An iodothyronine compound having iodo substituents at the 3-, 3'-, 5- and 5'-positions. | 1.96 | 1 | 0 | 2-halophenol;
iodophenol;
L-phenylalanine derivative;
non-proteinogenic L-alpha-amino acid;
thyroxine zwitterion;
thyroxine | antithyroid drug;
human metabolite;
mouse metabolite;
thyroid hormone |
dehydroepiandrosterone
Dehydroepiandrosterone: A major C19 steroid produced by the ADRENAL CORTEX. It is also produced in small quantities in the TESTIS and the OVARY. Dehydroepiandrosterone (DHEA) can be converted to TESTOSTERONE; ANDROSTENEDIONE; ESTRADIOL; and ESTRONE. Most of DHEA is sulfated (DEHYDROEPIANDROSTERONE SULFATE) before secretion.. dehydroepiandrosterone : An androstanoid that is androst-5-ene substituted by a beta-hydroxy group at position 3 and an oxo group at position 17. It is a naturally occurring steroid hormone produced by the adrenal glands. | 1.96 | 1 | 0 | 17-oxo steroid;
3beta-hydroxy-Delta(5)-steroid;
androstanoid | androgen;
human metabolite;
mouse metabolite |
sulfamic acid
sulfamic acid: standard in alkalimetry; RN given refers to parent cpd; structure. sulfamic acid : The simplest of the sulfamic acids consisting of a single sulfur atom covalently bound by single bonds to hydroxy and amino groups and by double bonds to two oxygen atoms. | 2 | 1 | 0 | sulfamic acids | |
aniline
[no description available] | 2.03 | 1 | 0 | anilines;
primary arylamine | |
chloroform
Chloroform: A commonly used laboratory solvent. It was previously used as an anesthetic, but was banned from use in the U.S. due to its suspected carcinogenicity.. chloroform : A one-carbon compound that is methane in which three of the hydrogens are replaced by chlorines. | 1.98 | 1 | 0 | chloromethanes;
one-carbon compound | carcinogenic agent;
central nervous system drug;
inhalation anaesthetic;
non-polar solvent;
refrigerant |
17-alpha-hydroxyprogesterone
17alpha-hydroxyprogesterone : A 17alpha-hydroxy steroid that is the 17alpha-hydroxy derivative of progesterone. | 1.96 | 1 | 0 | 17alpha-hydroxy-C21-steroid;
17alpha-hydroxy steroid;
tertiary alpha-hydroxy ketone | human metabolite;
metabolite;
mouse metabolite;
progestin |
brompheniramine
Brompheniramine: Histamine H1 antagonist used in treatment of allergies, rhinitis, and urticaria.. brompheniramine : Pheniramine in which the hydrogen at position 4 of the phenyl substituent is substituted by bromine. A histamine H1 receptor antagonist, brompheniramine is used (commonly as its maleate salt) for the symptomatic relief of allergic conditions, including rhinitis and conjunctivitis. | 2.44 | 2 | 0 | organobromine compound;
pyridines | anti-allergic agent;
H1-receptor antagonist |
2-toluidine
2-toluidine: RN given refers to parent cpd. o-toluidine : An aminotoluene in which the amino substituent is ortho to the methyl group. | 2.03 | 1 | 0 | aminotoluene | carcinogenic agent |
tripropylamine
tripropylammonium: RN given refers to parent cpd. tripropylamine : A tertiary amine that is ammonia in which each hydrogen atom is substituted by a propyl group. | 2.13 | 1 | 0 | tertiary amine | |
pyrroles
1H-pyrrole : A tautomer of pyrrole that has the double bonds at positions 2 and 4.. pyrrole : A five-membered monocyclic heteroarene comprising one NH and four CH units which forms the parent compound of the pyrrole group of compounds. Its five-membered ring structure has three tautomers. A 'closed class'.. azole : Any monocyclic heteroarene consisting of a five-membered ring containing nitrogen. Azoles can also contain one or more other non-carbon atoms, such as nitrogen, sulfur or oxygen. | 2 | 1 | 0 | pyrrole;
secondary amine | |
acridines
Acridines: Compounds that include the structure of acridine.. acridine : A polycyclic heteroarene that is anthracene in which one of the central CH groups is replaced by a nitrogen atom. | 3.77 | 3 | 0 | acridines;
mancude organic heterotricyclic parent;
polycyclic heteroarene | genotoxin |
hydrazine
diamine : Any polyamine that contains two amino groups. | 1.97 | 1 | 0 | azane;
hydrazines | EC 4.3.1.10 (serine-sulfate ammonia-lyase) inhibitor |
medroxyprogesterone
[no description available] | 6.97 | 1 | 0 | 17alpha-hydroxy steroid;
20-oxo steroid;
3-oxo-Delta(4) steroid;
tertiary alpha-hydroxy ketone | contraceptive drug;
progestin;
synthetic oral contraceptive |
luminol
Luminol: 5-Amino-2,3-dihydro-1,4-phthalazinedione. Substance that emits light on oxidation. It is used in chemical determinations. | 6.91 | 54 | 0 | | |
4-iodophenol
[no description available] | 1.99 | 1 | 0 | iodophenol | |
dehydroepiandrosterone sulfate
Dehydroepiandrosterone Sulfate: The circulating form of a major C19 steroid produced primarily by the ADRENAL CORTEX. DHEA sulfate serves as a precursor for TESTOSTERONE; ANDROSTENEDIONE; ESTRADIOL; and ESTRONE.. dehydroepiandrosterone sulfate : A steroid sulfate that is the 3-sulfooxy derivative of dehydroepiandrosterone. | 1.96 | 1 | 0 | 17-oxo steroid;
steroid sulfate | EC 2.7.1.33 (pantothenate kinase) inhibitor;
human metabolite;
mouse metabolite |
deoxycytidine
[no description available] | 1.97 | 1 | 0 | pyrimidine 2'-deoxyribonucleoside | Escherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite |
fluorescein
Fluorescein: A phthalic indicator dye that appears yellow-green in normal tear film and bright green in a more alkaline medium such as the aqueous humor.. fluorescein (lactone form) : A xanthene dye that is highly fluorescent, detectable even when present in minute quantities. Used forensically to detect traces of blood, in analytical chemistry as an indicator in silver nitrate titrations and in microscopy. | 3.06 | 1 | 0 | 2-benzofurans;
gamma-lactone;
organic heteropentacyclic compound;
oxaspiro compound;
polyphenol;
xanthene dye | fluorescent dye;
radioopaque medium |
gold
Gold: A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts. | 2.6 | 1 | 0 | copper group element atom;
elemental gold | |
tetradecanoylphorbol acetate
Tetradecanoylphorbol Acetate: A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.. phorbol ester : Esters of phorbol, originally found in croton oil (from Croton tiglium, of the family Euphorbiaceae). A number of phorbol esters possess activity as tumour promoters and activate the mechanisms associated with cell growth. Some of these are used in experiments as activators of protein kinase C.. phorbol 13-acetate 12-myristate : A phorbol ester that is phorbol in which the hydroxy groups at the cyclopropane ring juction (position 13) and the adjacent carbon (position 12) have been converted into the corresponding acetate and myristate esters. It is a major active constituent of the seed oil of Croton tiglium. It has been used as a tumour promoting agent for skin carcinogenesis in rodents and is associated with increased cell proliferation of malignant cells. However its function is controversial since a decrease in cell proliferation has also been observed in several cancer cell types. | 2.4 | 2 | 0 | acetate ester;
diester;
phorbol ester;
tertiary alpha-hydroxy ketone;
tetradecanoate ester | antineoplastic agent;
apoptosis inducer;
carcinogenic agent;
mitogen;
plant metabolite;
protein kinase C agonist;
reactive oxygen species generator |
transferrin
Transferrin: An iron-binding beta1-globulin that is synthesized in the LIVER and secreted into the blood. It plays a central role in the transport of IRON throughout the circulation. A variety of transferrin isoforms exist in humans, including some that are considered markers for specific disease states. | 1.99 | 1 | 0 | | |
sodium azide
Sodium Azide: A cytochrome oxidase inhibitor which is a nitridizing agent and an inhibitor of terminal oxidation. (From Merck Index, 12th ed). sodium azide : The sodium salt of hydrogen azide (hydrazoic acid). | 1.96 | 1 | 0 | inorganic sodium salt | antibacterial agent;
explosive;
mitochondrial respiratory-chain inhibitor;
mutagen |
azides
Azides: Organic or inorganic compounds that contain the -N3 group.. azide : Any nitrogen molecular entity containing the group -N3. | 1.96 | 1 | 0 | pseudohalide anion | mitochondrial respiratory-chain inhibitor |
3,3',5,5'-tetramethylbenzidine
T1023: radioprotective NO-Synthase Inhibitor | 1.96 | 1 | 0 | | |
glucose, (beta-d)-isomer
beta-D-glucose : D-Glucopyranose with beta configuration at the anomeric centre.. (1->4)-beta-D-glucan : A beta-D-glucan in which the glucose units are connected by (1->4) linkages.. (1->3)-beta-D-glucan : A beta-D-glucan in which the glucose units are connected by (1->3) linkages. | 2.39 | 2 | 0 | D-glucopyranose | epitope;
mouse metabolite |
10,10'-dimethyl-9,9'-biacridinium
10,10'-dimethyl-9,9'-biacridinium: chemoluminescent probe; RN given refers to dinitrate; Lucigenin refers to dinitrate | 3.77 | 3 | 0 | | |
5-bromo-4-chloro-3-indolyl beta-galactoside
5-bromo-4-chloro-3-indolyl beta-galactoside: enzyme substrate for beta-galactosidase. 5-bromo-4-chloro-3-indolyl beta-D-galactoside : An indolyl carbohydrate that is the beta-D-galactoside of 3-hydroxy-1H-indole in which the indole moiety is substituted at positions 4 and 5 by chlorine and bromine, respectively. It is used to test for the presence of an enzyme, beta-galactosidase, which cleaved the glycosidic bond to give 5-bromo-4-chloro-3-hydroxy-1H-indole, which immediately dimerises to give an intensely blue product. | 1.97 | 1 | 0 | beta-D-galactoside;
D-aldohexose derivative;
indolyl carbohydrate;
organobromine compound;
organochlorine compound | chromogenic compound |
tris(2,2'-bipyridine)ruthenium(II)
tris(2,2'-bipyridyl)ruthenium(II): a fluorescent dye; structure in first source | 2.13 | 1 | 0 | ruthenium coordination entity | fluorochrome |
5-bromo-4-chloro-3-indoxyl phosphate
5-bromo-4-chloro-3-indoxyl phosphate: substrate for demonstration of activity of alkaline phosphatase; structure given in first source. 5-bromo-4-chloro-3-indolyl phosphate : An aryl phosphate that is indoxyl phopshate in which the indole moiety is substituted at positions 4 and 5 by chlorine and bromine, respectively. It is used to test for the presence of an enzyme, alkaline phosphatase, which cleaves the phosphate group to give 5-bromo-4-chloroindoxyl, which immediately dimerises to give an intensely blue product. | 1.97 | 1 | 0 | aryl phosphate;
indoles;
organobromine compound;
organochlorine compound | chromogenic compound |
4-bromophenylboric acid
[no description available] | 1.99 | 1 | 0 | | |
nicotine
(S)-nicotine : A 3-(1-methylpyrrolidin-2-yl)pyridine in which the chiral centre has S-configuration. The naturally occurring and most active enantiomer of nicotine, isolated from Nicotiana tabacum. | 2.06 | 1 | 0 | 3-(1-methylpyrrolidin-2-yl)pyridine | anxiolytic drug;
biomarker;
immunomodulator;
mitogen;
neurotoxin;
nicotinic acetylcholine receptor agonist;
peripheral nervous system drug;
phytogenic insecticide;
plant metabolite;
psychotropic drug;
teratogenic agent;
xenobiotic |
firefly luciferin
Firefly Luciferin: A benzothaizole which is oxidized by LUCIFERASES, FIREFLY to cause emission of light (LUMINESCENCE).. Photinus luciferin : A 1,3-thiazolemonocarboxylic acid consisting of 3,5-dihydrothiophene-4-carboxylic acid having a 6-hydroxybenzothiazol-2-yl group at the 2-position. | 3.48 | 2 | 0 | 1,3-thiazolemonocarboxylic acid;
benzothiazoles;
imidothioate | luciferin |
cobalt
Cobalt: A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.. cobalt(1+) : A monovalent inorganic cation obtained from cobalt.. cobalt atom : A cobalt group element atom that has atomic number 27. | 2.05 | 1 | 0 | cobalt group element atom;
metal allergen | micronutrient |
4-iodophenylboronic acid
4-iodophenylboronic acid: structure given in first source; selectively concentrates in some cancer cells | 1.99 | 1 | 0 | | |
9-(4'-aminophenyl)-9h-pyrido(3,4-b)indole
9-(4'-aminophenyl)-9H-pyrido(3,4-b)indole: structure in first source | 2.03 | 1 | 0 | | |
hydroxyl radical
Hydroxyl Radical: The univalent radical OH. Hydroxyl radical is a potent oxidizing agent. | 2 | 1 | 0 | oxygen hydride;
oxygen radical;
reactive oxygen species | |
singlet oxygen
Singlet Oxygen: An excited state of molecular oxygen generated photochemically or chemically. Singlet oxygen reacts with a variety of biological molecules such as NUCLEIC ACIDS; PROTEINS; and LIPIDS; causing oxidative damages. | 2.41 | 2 | 0 | chalcogen;
monoatomic oxygen;
nonmetal atom | macronutrient |
biotin
vitamin B7 : Any member of a group of vitamers that belong to the chemical structural class called biotins that exhibit biological activity against vitamin B7 deficiency. Vitamin B7 deficiency is very rare in individuals who take a normal balanced diet. Foods rich in biotin are egg yolk, liver, cereals, vegetables (spinach, mushrooms) and rice. Symptoms associated with vitamin B7 deficiency include thinning hair, scaly skin rashes around eyes, nose and mouth, and brittle nails. The vitamers include biotin and its ionized and salt forms. | 1.97 | 1 | 0 | biotins;
vitamin B7 | coenzyme;
cofactor;
Escherichia coli metabolite;
fundamental metabolite;
human metabolite;
mouse metabolite;
nutraceutical;
prosthetic group;
Saccharomyces cerevisiae metabolite |
n-formylmethionine leucyl-phenylalanine
N-Formylmethionine Leucyl-Phenylalanine: A formylated tripeptide originally isolated from bacterial filtrates that is positively chemotactic to polymorphonuclear leucocytes, and causes them to release lysosomal enzymes and become metabolically activated.. N-formyl-L-methionyl-L-leucyl-L-phenylalanine : A tripeptide composed of L-Met, L-Leu and L-Phe in a linear sequence with a formyl group at the amino terminus. It acts as a potent inducer of leucocyte chemotaxis and macrophage activator as well as a ligand for the FPR receptor. | 1.99 | 1 | 0 | tripeptide | |
cotinine
Cotinine: The N-glucuronide conjugate of cotinine is a major urinary metabolite of NICOTINE. It thus serves as a biomarker of exposure to tobacco SMOKING. It has CNS stimulating properties.. (-)-cotinine : An N-alkylpyrrolidine that consists of N-methylpyrrolidinone bearing a pyridin-3-yl substituent at position C-5 (the 5S-enantiomer). It is an alkaloid commonly found in Nicotiana tabacum. | 2.06 | 1 | 0 | N-alkylpyrrolidine;
pyridines;
pyrrolidin-2-ones;
pyrrolidine alkaloid | antidepressant;
biomarker;
human xenobiotic metabolite;
plant metabolite |
zeranol
Zeranol: A non-steroidal estrogen analog. | 7.37 | 2 | 0 | macrolide | |
zearalenone
Zearalenone: (S-(E))-3,4,5,6,8,10-Hexahydro-14,16-dihydroxy-3-methyl-1H-2-benzoxacyclotetradecin-1,7(8H)-dione. One of a group of compounds known under the general designation of resorcylic acid lactones. Cis, trans, dextro and levo forms have been isolated from the fungus Gibberella zeae (formerly Fusarium graminearum). They have estrogenic activity, cause toxicity in livestock as feed contaminant, and have been used as anabolic or estrogen substitutes.. zearalenone : A macrolide comprising a fourteen-membered lactone fused to 1,3-dihydroxybenzene; a potent estrogenic metabolite produced by some Giberella species. | 1.96 | 1 | 0 | macrolide;
resorcinols | fungal metabolite;
mycoestrogen |
progesterone 11-hemisuccinate, (11alpha)-isomer
progesterone 11-hemisuccinate: RN given refers to cpd without isomeric designation | 2.36 | 2 | 0 | 20-oxo steroid;
3-oxo-Delta(4) steroid;
dicarboxylic acid monoester;
hemisuccinate;
steroid ester | |
oxalates
Oxalates: Derivatives of OXALIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that are derived from the ethanedioic acid structure. | 3.06 | 1 | 0 | | |
dithiadene
dithiadene: minor descriptor (75-85); on-line & Index Medicus search DIBENZOTHIEPINS (69-74) & BENZOTHIEPINS (75-85); RN given refers to parent cpd without isomeric designation. dithiadene : An organic heterotricyclic compound that is 4,9-dihydrothieno[2,3-c][2]benzothiepine substituted by a 3-(dimethylamino)propylidene group at position 4. | 2.43 | 2 | 0 | dithiadene | |
ubiquinol
ubiquinol: reduced forms of ubiquinone; see also record for ubiquinol 10. ubiquinol-10 : A ubiquinol in which the polyprenyl substituent is decaprenyl. | 1.97 | 1 | 0 | polyprenylhydroquinone;
ubiquinol | biomarker;
metabolite |
nad
NAD(1-) : An anionic form of nicotinamide adenine dinucleotide arising from deprotonation of the two OH groups of the diphosphate moiety. | 3.06 | 1 | 0 | organophosphate oxoanion | cofactor;
human metabolite;
hydrogen acceptor;
Saccharomyces cerevisiae metabolite |
ubiquinone
Ubiquinone: A lipid-soluble benzoquinone which is involved in ELECTRON TRANSPORT in mitochondrial preparations. The compound occurs in the majority of aerobic organisms, from bacteria to higher plants and animals. | 1.97 | 1 | 0 | | |
guanine
[no description available] | 2 | 1 | 0 | 2-aminopurines;
oxopurine;
purine nucleobase | algal metabolite;
Escherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite |
2-amino-4-hydroxypteridine
[no description available] | 2.01 | 1 | 0 | 2-amino-4-hydroxypteridine;
pterin | |
queuine
[no description available] | 2 | 1 | 0 | pyrrolopyrimidine | Escherichia coli metabolite |
pyrimidinones
Pyrimidinones: Heterocyclic compounds known as 2-pyrimidones (or 2-hydroxypyrimidines) and 4-pyrimidones (or 4-hydroxypyrimidines) with the general formula C4H4N2O. | 2 | 1 | 0 | | |