Page last updated: 2024-10-24
type I pneumocyte differentiation
Definition
Target type: biologicalprocess
The process in which a relatively unspecialized cell acquires specialized features of a type I pneumocyte. A type I pneumocyte is a flattened cell with greatly attenuated cytoplasm and a paucity of organelles. [GOC:dph, GOC:mtg_lung, ISBN:0721662544]
Type I pneumocyte differentiation is a complex developmental process that begins with the commitment of progenitor cells to the alveolar epithelial lineage. These progenitor cells, known as alveolar type II (ATII) cells, express surfactant proteins and have the capacity to self-renew and differentiate into both ATII and type I alveolar epithelial cells (ATI).
ATI cells are the primary gas exchange cells in the alveoli, characterized by their thin, flattened morphology and tight junctions that create a continuous barrier between the air and the blood. The differentiation of ATII cells into ATI cells involves a series of coordinated molecular events, including changes in gene expression, cell morphology, and cell-cell interactions.
The process of type I pneumocyte differentiation is regulated by a complex network of signaling pathways, including growth factors, transcription factors, and extracellular matrix components. For example, the Wnt signaling pathway has been shown to play a crucial role in promoting ATII cell differentiation into ATI cells. Similarly, the transcription factor GATA6 is essential for the expression of genes required for ATI cell function.
During differentiation, ATII cells undergo significant morphological changes. They flatten and spread, extending thin cytoplasmic processes that form tight junctions with adjacent cells. These changes in cell shape are driven by cytoskeletal rearrangements and the expression of specific adhesion molecules.
As ATI cells mature, they express a unique set of proteins that are essential for their function. These proteins include aquaporin 5, which facilitates water transport across the alveolar epithelium, and the sodium-potassium pump, which maintains ion gradients and regulates cell volume.
Type I pneumocyte differentiation is an essential process for lung development and function. Defects in this process can lead to lung diseases such as bronchopulmonary dysplasia and alveolar proteinosis. Understanding the molecular mechanisms that regulate type I pneumocyte differentiation is crucial for developing new therapies for these diseases.'
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Proteins (5)
| Protein | Definition | Taxonomy |
|---|---|---|
| Cyclic AMP-responsive element-binding protein 1 | A cyclic AMP-responsive element-binding protein 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P16220] | Homo sapiens (human) |
| Thyroid hormone receptor beta | A thyroid hormone receptor beta that is encoded in the genome of human. [PRO:DNx, UniProtKB:P10828] | Homo sapiens (human) |
| Thyroid hormone receptor alpha | A thyroid hormone receptor alpha that is encoded in the genome of human. [PRO:HJD, UniProtKB:P10827] | Homo sapiens (human) |
| Leukotriene A-4 hydrolase | A leukotriene A-4 hydrolase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P09960] | Homo sapiens (human) |
| GTPase KRas | A GTPase KRas that is encoded in the genome of human. [PRO:DNx, UniProtKB:P01116] | Homo sapiens (human) |
Compounds (71)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| amiodarone | amiodarone : A member of the class of 1-benzofurans that is 1-benzofuran substituted by a butyl group at position 2 and a 4-[2-(diethylamino)ethoxy]-3,5-diiodobenzoyl group at position 3. It is a cardiovascular drug used for the treatment of cardiac dysrhythmias. Amiodarone: An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance. | 1-benzofurans; aromatic ketone; organoiodine compound; tertiary amino compound | cardiovascular drug |
| 4-(dimethylamino)-n-(7-(hydroxyamino)-7-oxoheptyl)benzamide | 4-(dimethylamino)-N-(7-(hydroxyamino)-7-oxoheptyl)benzamide: structure in first source 4-(dimethylamino)-N-[7-(hydroxyamino)-7-oxoheptyl]benzamide : A benzamide resulting from the formal condensation of the carboxy group of 4-(dimethylamino)benzoic acid with the amino group of 7-amino-N-hydroxyheptanamide. It is a potent inhibitor of histone deacetylases and induces cell cycle arrest and apoptosis in several human cancer cell lines. | benzamides; hydroxamic acid; secondary carboxamide; tertiary amino compound | antineoplastic agent; apoptosis inducer; EC 3.5.1.98 (histone deacetylase) inhibitor |
| entinostat | benzamides; carbamate ester; primary amino compound; pyridines; substituted aniline | antineoplastic agent; apoptosis inducer; EC 3.5.1.98 (histone deacetylase) inhibitor | |
| nimesulide | nimesulide : An aromatic ether having phenyl and 2-methylsulfonamido-5-nitrophenyl as the two aryl groups. nimesulide: structure | aromatic ether; C-nitro compound; sulfonamide | cyclooxygenase 2 inhibitor; non-steroidal anti-inflammatory drug |
| scriptaid | scriptide: provokes translocation of GLUT4 to increase glucose uptake; structure in first source | isoquinolines | |
| vorinostat | vorinostat : A dicarboxylic acid diamide comprising suberic (octanedioic) acid coupled to aniline and hydroxylamine. A histone deacetylase inhibitor, it is marketed under the name Zolinza for the treatment of cutaneous T cell lymphoma (CTCL). Vorinostat: A hydroxamic acid and anilide derivative that acts as a HISTONE DEACETYLASE inhibitor. It is used in the treatment of CUTANEOUS T-CELL LYMPHOMA and SEZARY SYNDROME. | dicarboxylic acid diamide; hydroxamic acid | antineoplastic agent; apoptosis inducer; EC 3.5.1.98 (histone deacetylase) inhibitor |
| benzimidazole | 1H-benzimidazole : The 1H-tautomer of benzimidazole. | benzimidazole; polycyclic heteroarene | |
| 3,3',5-triiodothyroacetic acid | tiratricol : A monocarboxylic acid that is (4-hydroxy-3,5-diiodophenyl)acetic acid in which the phenolic hydroxy group has been replaced by a 4-hydroxy-3-iodophenoxy group. It is a thyroid hormone analogue that has been used in the treatment of thyroid hormone resistance syndrome. | ||
| 3,3',5-triiodothyropropionic acid | aromatic ether | ||
| thyroxine | thyroxine : An iodothyronine compound having iodo substituents at the 3-, 3'-, 5- and 5'-positions. 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. | 2-halophenol; iodophenol; L-phenylalanine derivative; non-proteinogenic L-alpha-amino acid; thyroxine; thyroxine zwitterion | antithyroid drug; human metabolite; mouse metabolite; thyroid hormone |
| triiodothyronine | 3,3',5-triiodo-L-thyronine : An iodothyronine compound having iodo substituents at the 3-, 3'- and 5-positions. Although some is produced in the thyroid, most of the 3,3',5-triiodo-L-thyronine in the body is generated by mono-deiodination of L-thyroxine in the peripheral tissues. Its metabolic activity is about 3 to 5 times that of L-thyroxine. The sodium salt is used in the treatment of hypothyroidism. Triiodothyronine: A T3 thyroid hormone normally synthesized and secreted by the thyroid gland in much smaller quantities than thyroxine (T4). Most T3 is derived from peripheral monodeiodination of T4 at the 5' position of the outer ring of the iodothyronine nucleus. The hormone finally delivered and used by the tissues is mainly T3. | 2-halophenol; amino acid zwitterion; iodophenol; iodothyronine | human metabolite; mouse metabolite; thyroid hormone |
| bisphenol a | 4,4'-isopropylidene diphenol: stimulates proliferative responses and cytokine productions of murine spleen cells and thymus cells in vitro bisphenol : By usage, the methylenediphenols, HOC6H4CH2C6H4OH, commonly p,p-methylenediphenol, and their substitution products (generally derived from condensation of two equivalent amounts of a phenol with an aldehyde or ketone). The term also includes analogues in the the methylene (or substituted methylene) group has been replaced by a heteroatom. bisphenol A : A bisphenol that is 4,4'-methanediyldiphenol in which the methylene hydrogens are replaced by two methyl groups. | bisphenol | endocrine disruptor; environmental contaminant; xenobiotic; xenoestrogen |
| phenyl ether | diphenyl ether : An aromatic ether in which the oxygen is attached to two phenyl substituents. It has been found in muscat grapes and vanilla. | aromatic ether | plant metabolite |
| 4-phenoxyphenol | phenoxyphenol | ||
| 5-hydroxyindole | hydroxyindoles | human metabolite | |
| 2-aminotetralin | 2-aminotetralin: RN given refers to parent cpd without isomeric designation; structure | tetralins | |
| captopril | captopril : A L-proline derivative in which L-proline is substituted on nitrogen with a (2S)-2-methyl-3-sulfanylpropanoyl group. It is used as an anti-hypertensive ACE inhibitor drug. Captopril: A potent and specific inhibitor of PEPTIDYL-DIPEPTIDASE A. It blocks the conversion of ANGIOTENSIN I to ANGIOTENSIN II, a vasoconstrictor and important regulator of arterial blood pressure. Captopril acts to suppress the RENIN-ANGIOTENSIN SYSTEM and inhibits pressure responses to exogenous angiotensin. | alkanethiol; L-proline derivative; N-acylpyrrolidine; pyrrolidinemonocarboxylic acid | antihypertensive agent; EC 3.4.15.1 (peptidyl-dipeptidase A) inhibitor |
| mifepristone | Mifepristone: A progestational and glucocorticoid hormone antagonist. Its inhibition of progesterone induces bleeding during the luteal phase and in early pregnancy by releasing endogenous prostaglandins from the endometrium or decidua. As a glucocorticoid receptor antagonist, the drug has been used to treat hypercortisolism in patients with nonpituitary CUSHING SYNDROME. | 3-oxo-Delta(4) steroid; acetylenic compound; tertiary amino compound | abortifacient; contraceptive drug; hormone antagonist; synthetic oral contraceptive |
| zileuton | 1-benzothiophenes; ureas | anti-asthmatic drug; EC 1.13.11.34 (arachidonate 5-lipoxygenase) inhibitor; ferroptosis inhibitor; leukotriene antagonist; non-steroidal anti-inflammatory drug | |
| tetraiodothyroacetic acid | 3,3',5,5'-tetraiodothyroacetic acid : A monocarboxylic acid that is thyroacetic acid carrying four iodo substituents at positions 3, 3', 5 and 5'. tetraiodothyroacetic acid: RN given refers to parent cpd; structure | 2-halophenol; aromatic ether; iodophenol; monocarboxylic acid | apoptosis inducer; human metabolite; thyroid hormone |
| 5-fluoroindole | fluoroindole | ||
| beta-tetralone | |||
| ubenimex | ubenimex: growth inhibitor | ||
| 5-chloroindole | 5-chloroindole: a positive allosteric modulator of the 5-HT3 receptor | ||
| 5-benzyloxytryptophan | |||
| tesmilifene | diarylmethane | ||
| 3,5-dimethyl-3'-isopropyl-l-thyronine | 3,5-dimethyl-3'-isopropyl-L-thyronine: RN given refers to (L)-isomer | ||
| kelatorphan | kelatorphan: inhibitor of enkephalin metabolism; structure given in first source | ||
| alanine-4-nitroanilide | alanine-4-nitroanilide: substrate for aminopeptidase M | ||
| pyrrolidino-benzylphenoxyethanamine | |||
| dihydroresveratrol | dihydroresveratrol : A stilbenol that is 1,1'-ethane-1,2-diyldibenzene with hydroxy groups at positions 1, 3 and 4'. dihydroresveratrol: structure in first source | stilbenol | plant metabolite; xenobiotic metabolite |
| 4-(2-Amino-1,3-thiazol-4-yl)phenol | phenols | ||
| trichostatin a | trichostatin A: chelates zinc ion in the active site of histone deacetylases, resulting in preventing histone unpacking so DNA is less available for transcription; do not confuse with TRICHOSANTHIN which is a protein; found in STREPTOMYCES | antibiotic antifungal agent; hydroxamic acid; trichostatin | bacterial metabolite; EC 3.5.1.98 (histone deacetylase) inhibitor; geroprotector |
| resveratrol | trans-resveratrol : A resveratrol in which the double bond has E configuration. | resveratrol | antioxidant; phytoalexin; plant metabolite; quorum sensing inhibitor; radical scavenger |
| bms 214662 | 7-cyano-2,3,4,5-tetrahydro-1-(1H-imidazol-4-ylmethyl)-3-(phenylmethyl)-4-(2-thienylsulfonyl)-1H-1,4-benzodiazepine: a farnesyltransferase inhibitor; structure in first source BMS-214662 : A member of the class of benzodiazepines that is 2,3,4,5-tetrahydro-1H-1,4-benzodiazepine substituted by (1H-imidazol-5-yl)methyl, benzyl, (thiophen-2-yl)sulfonyl, and cyano groups at positions 1, 3R, 4 and 7, respectively. It is a potent inhibitor of farnesyltransferase (IC50 = 1.35nM) which was under clinical development for the treatment of solid tumors. | benzenes; benzodiazepine; imidazoles; nitrile; sulfonamide; thiophenes | antineoplastic agent; apoptosis inducer; EC 2.5.1.58 (protein farnesyltransferase) inhibitor |
| leukotriene a4 | leukotriene A4 : A leukotriene that is the (5S,6S)-epoxy derivative of (7E,9E,11Z,14Z)-icosa-7,9,11,14-tetraenoic acid. Leukotriene A4: (2S-(2 alpha,3 beta(1E,3E,5Z,8Z)))-3-(1,3,5,8-Tetradecatetraenyl)oxiranebutanoic acid. An unstable allylic epoxide, formed from the immediate precursor 5-HPETE via the stereospecific removal of a proton at C-10 and dehydration. Its biological actions are determined primarily by its metabolites, i.e., LEUKOTRIENE B4 and cysteinyl-leukotrienes. Alternatively, leukotriene A4 is converted into LEUKOTRIENE C4 by glutathione-S-transferase or into 5,6-di-HETE by the epoxide-hydrolase. (From Dictionary of Prostaglandins and Related Compounds, 1990) | epoxy fatty acid; leukotriene; long-chain fatty acid; oxylipin; polyunsaturated fatty acid | human metabolite; mouse metabolite; plant metabolite |
| baicalein | trihydroxyflavone | angiogenesis inhibitor; anti-inflammatory agent; antibacterial agent; anticoronaviral agent; antifungal agent; antineoplastic agent; antioxidant; apoptosis inducer; EC 1.13.11.31 (arachidonate 12-lipoxygenase) inhibitor; EC 1.13.11.33 (arachidonate 15-lipoxygenase) inhibitor; EC 3.4.21.26 (prolyl oligopeptidase) inhibitor; EC 3.4.22.69 (SARS coronavirus main proteinase) inhibitor; EC 4.1.1.17 (ornithine decarboxylase) inhibitor; ferroptosis inhibitor; geroprotector; hormone antagonist; plant metabolite; prostaglandin antagonist; radical scavenger | |
| shogaol | shogaol: from ginger, ZINGIBER OFFICINALE; less mutagenic than GINGEROL; structure given in first source | enone; monomethoxybenzene; phenols | |
| 5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one | 5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one: isolated from the Chinese herb Scutellariae radix oroxylin A : A dihydroxy- and monomethoxy-flavone in which the hydroxy groups are positioned at C-5 and C-7 and the methoxy group is at C-6. | dihydroxyflavone; monomethoxyflavone | antineoplastic agent; EC 1.14.13.39 (nitric oxide synthase) inhibitor |
| manumycin | manumycin A : A polyketide with formula C31H38N2O7 initially isolated from Streptomyces parvulus as a result of a random screening program for farnesyl transferase (FTase) inhibitors. It is a natural product that exhibits anticancer and antibiotic properties. manumycin: an NSAID; RN given for (1S-(1alpha,3(2E,4E,6S*),5alpha,5(1E,3E,5E),6alpha))-isomer; a farnesyl protein transferase inhibitor; from Streptomyces parvulus; MF C31-H38-N2-O7; structure given in first source | enamide; epoxide; organic heterobicyclic compound; polyketide; secondary carboxamide; tertiary alcohol | antiatherosclerotic agent; antimicrobial agent; antineoplastic agent; apoptosis inducer; bacterial metabolite; EC 1.8.1.9 (thioredoxin reductase) inhibitor; EC 2.5.1.58 (protein farnesyltransferase) inhibitor; marine metabolite |
| pregna-4,17-diene-3,16-dione | pregna-4,17-diene-3,16-dione: steroid from guggulu extract; RN & N1 from C1 Form index; RN given refers to cpd without isomeric designation; structure in first source; antagonist of farnesoid X receptor | 3-hydroxy steroid | androgen |
| tubacin | tubacin: inhibits histone deacetylase 6; structure in first source | 1,3-oxazoles | |
| belinostat | hydroxamic acid; olefinic compound; sulfonamide | antineoplastic agent; EC 3.5.1.98 (histone deacetylase) inhibitor | |
| panobinostat | panobinostat : A hydroxamic acid obtained by formal condensation of the carboxy group of (2E)-3-[4-({[2-(2-methylindol-3-yl)ethyl]amino}methyl)phenyl]prop-2-enoic acid with the amino group of hydroxylamine. A histone deacetylase inhibitor used (as its lactate salt) in combination with bortezomib and dexamethasone for the treatment of multiple myeloma. Panobinostat: An indole and hydroxamic acid derivative that acts as a HISTONE DEACETYLASE inhibitor. It is used as an antineoplastic agent in combination with BORTEZOMIB and DEXAMETHASONE for the treatment of MULTIPLE MYELOMA. | cinnamamides; hydroxamic acid; methylindole; secondary amino compound | angiogenesis modulating agent; antineoplastic agent; EC 3.5.1.98 (histone deacetylase) inhibitor |
| givinostat | carbamate ester | ||
| sc 57461 | SC 57461: a leukotriene A4 hydrolase inhibitor; structure given in first source | ||
| sc 57461 | |||
| ala-thr-trp-leu-pro-pro-arg | |||
| gc 1 compound | GC 1 compound: structure in first source | diarylmethane | |
| kb 141 | KB 141: an anticholesteremic agent; structure in first source | ||
| mocetinostat | mocetinostat : A benzamide obtained by formal condensation of the carboxy group of 4-({[4-(pyridin-3-yl)pyrimidin-2-yl]amino}methyl)benzoic acid with one of the amino groups of benzene-1,2-diamine. It is an orally active and isotype-selective HDAC inhibitor which exhibits antitumour activity (IC50 = 0.15, 0.29, 1.66 and 0.59 muM for HDAC1, HDAC2, HDAC3 and HDAC11). mocetinostat: undergoing phase II clinical trials for treatment of cancer | aminopyrimidine; benzamides; pyridines; secondary amino compound; secondary carboxamide; substituted aniline | antineoplastic agent; apoptosis inducer; autophagy inducer; cardioprotective agent; EC 3.5.1.98 (histone deacetylase) inhibitor; hepatotoxic agent |
| kb 130015 | KB 130015: structure in first source | ||
| cgs 23425 | CGS 23425: structure given in first source | ||
| 3,5-dibromo-4-(4-hydroxy-3-isopropylphenoxy)phenylacetic acid | 3,5-dibromo-4-(4-hydroxy-3-isopropylphenoxy)phenylacetic acid: a thyroid receptor beta1 agonist; structure in first source | ||
| kb 2115 | 3-((3,5-dibromo-4-(4-hydroxy-3-(1-methylethyl)phenoxy)phenyl)amino)-3-oxopropanoic acid: a thyroid hormone receptor agonist with anticholesteremic activity | ||
| fg-4592 | roxadustat : An N-acylglycine resulting from the formal condensation of the amino group of glycine with the carboxy group of 4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxylic acid. It is an inhibitor of hypoxia inducible factor prolyl hydroxylase (HIF-PH). roxadustat: structure in first source | aromatic ether; isoquinolines; N-acylglycine | EC 1.14.11.2 (procollagen-proline dioxygenase) inhibitor; EC 1.14.11.29 (hypoxia-inducible factor-proline dioxygenase) inhibitor |
| quisinostat | indoles | ||
| resminostat | resminostat: a histone deacetylase inhibitor; structure in first source | ||
| abexinostat | abexinostat: structure in first source | benzofurans | |
| mgl-3196 | resmetirom: a thyroid hormone receptor-beta agonist | ||
| sch 54292 | SCH 54292: structure in first source | ||
| valproate sodium | Epilim: oral sodium valproate used as antidepressive agent sodium valproate : The sodium salt of valproic acid. valproate : A branched-chain saturated fatty acid anion that is the conjugate base of valproic acid. | organic sodium salt | geroprotector |
| cudc 101 | 7-(4-(3-ethynylphenylamino)-7-methoxyquinazolin-6-yloxy)-N-hydroxyheptanamide: a histone deacetylase inhibitor; structure in first source | ||
| plx4032 | aromatic ketone; difluorobenzene; monochlorobenzenes; pyrrolopyridine; sulfonamide | antineoplastic agent; B-Raf inhibitor | |
| dabrafenib | 1,3-thiazoles; aminopyrimidine; organofluorine compound; sulfonamide | anticoronaviral agent; antineoplastic agent; B-Raf inhibitor | |
| pracinostat | pracinostat : A hydroxamic acid that is N-hydroxyacrylamide which is substituted at position 3 by a 2-butyl-1-[2-(diethylamino)ethyl]-1H-benzimidazol-5-yl group (the E isomer). An orally available pan-histone deacetylase inhibitor with demonstrated activity in the treatment of advanced solid tumours. | benzimidazole; hydroxamic acid; olefinic compound; tertiary amino compound | antimalarial; antineoplastic agent; apoptosis inducer; EC 3.5.1.98 (histone deacetylase) inhibitor |
| acy-1215 | ricolinostat: an HDAC6 inhibitor; structure in first source | pyrimidinecarboxylic acid | |
| rg2833 | RG2833: a histone deacetylase inhibitor; structure in first source | ||
| ly3009120 | LY3009120 : A member of the class of pyridopyrimidines that is pyrido[2,3-d]pyrimidine substituted by methylamino, 5-{[(3,3-dimethylbutyl)carbamoyl]amino}-4-fluoro-2-methylphenyl, and methyl groups at positions 2, 6 and 7, respectively. It is a potent pan RAF inhibitor which inhibits BRAF(V600E), BRAF(WT) and CRAF(WT) (IC50 = 5.8, 9.1 and 15 nM, respectively). It also inhibits RAF homo- and heterodimers and exhibits anti-cancer properties. LY3009120: a pan-RAF inhibitor; structure in first source | aminotoluene; aromatic amine; biaryl; monofluorobenzenes; phenylureas; pyridopyrimidine; secondary amino compound | antineoplastic agent; apoptosis inducer; autophagy inducer; B-Raf inhibitor; necroptosis inhibitor |
| ARS-1620 | ARS-1620 : A qinazoline derivative carrying chloro and fluoro substituents at positions 6 and 8 respectively, a 2-fluoro-6-hydroxyphenyl group at position 7, and a 4-(prop-2-enoyl)piperazin-1-yl group at position 4. A potent, selective, and orally bioavailable covalent KRAS-G12C inhibitor, it inhibits the protein coding gene KRAS (Kirsten rat sarcoma virus) with high potency in cells and animals. ARS-1620: covalent S-IIP G12C inhibitor for targeting of KRAS G12C mutant tumors | quinazolines | antineoplastic agent; antiviral agent; inhibitor |
| sotorasib | sotorasib : A pyridopyrimidine that is pyrido[2,3-d]pyrimidin-2(1H)-one substituted by 4-methyl-2-(propan-2-yl)pyridin-3-yl, (2S)-2-methyl-4-(prop-2-enoyl)piperazin-1-yl, fluoro and 2-fluoro-6-hydroxyphenyl groups at positions 1, 4, 6 and 7, respectively. It is approved for the treatment of patients with non-small cell lung cancer having KRAS(G12C) mutations. sotorasib: a KRAS(G12C) inhibitor | acrylamides; methylpyridines; monofluorobenzenes; N-acylpiperazine; phenols; pyridopyrimidine; tertiary amino compound; tertiary carboxamide | antineoplastic agent |