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Journal of Molecular Structure
journalhomepage:www.elsevier.com/locate/molstr
Design, Synthesis, Analysis, Evaluation of Cytotoxicity Against MCF-7 Breast Cancer Cells, 3D QSAR Studies and EGFR, HER2 Inhibition Studies on Novel Biginelli 1,4-Dihydropyrimidines
Namburu Lalitha Naishima
a, Syed Faizan
a, Ruby Mariam Raju
a,
Aki Satya Venkata Lakshmi Sruthi
a, Veena NG
a, Gyanedra Kumar Sharma
b,
Kumar S Vasanth
c, Vasanth Kumar Shivaraju
d, Ramith Ramu
e, BR Prashantha Kumar
a,∗aDepartment of Pharmaceutical Chemistry, JSS College of Pharmacy, Mysuru 570015. Constituent College of JSS Academy of Higher Education & Research, Mysuru 570015. India
bDepartment of Pharmaceutical Chemistry, Anand College of Pharmacy, Agra. India
cDepartment of Mathematics, Mangalore Institute of Technology & Engineering, Moodbidri, India
dDOS in Chemistry, Karnataka State Open University, Mukthagangothri, Mysuru 570 0 06, India
eFaculty of Life Sciences, JSS Academy of Higher Education & Research, Mysuru 570 015. India
a rt i c l e i nf o
Article history:
Received 20 October 2022 Revised 19 December 2022 Accepted 20 December 2022 Available online 21 December 2022 Keywords:
Biginelli 1,4-dihydropyrimidines Anticancer activity
Cytotoxicity EGFR HER2 MCF-7 cells 3D-QSAR CoMSIA
a b s t r a c t
1,4-Dihydropyrimidinesareusuallysynthesizedfrom Biginellireactionwhicharewell knownfortheir anti-cancer activity.A series ofnovel Biginelli-1,4-dihydropyrimidines arerationally designed, synthe- sized,purified,analyzedbyIR,NMR,MassspectrometryandscreenedagainstMCF-7breastcancercells fortheiranti-canceractivitybymeasuringthecytotoxicity.Dihydropyrimidinesexhibitedweaktosignifi- cantcytotoxicityproportionatetotheiranti-canceractivity.14,7and5haveexhibitedpotentcytotoxicity amongstthescreened33dihydropyrimidines.Mostpotentcompound14isfurthertestedforinhibitionof EGFR(epidermalgrowthfactorreceptor)andHER2(humanepidermalgrowthfactorreceptor2)expres- sionat2differentconcentrationsbytakinglapatinibasstandardinflowcytometry.42.02%and36.45%of cellsexpressingEGFRandHER2wereinhibitedat500nM/Lconcentration.Furthermore,3D-QSARstudies wereexecutedtoelucidatestructureactivityrelationshipsina3Dgridspacebyplottingexperimentalvs predictedcytotoxicactivities.
© 2022ElsevierB.V.Allrightsreserved.
1. Introduction
Research for novelty is a challenging, high-priced and long- termprocedure withcompilation ofmanyaspects involvingvari- ous componentsfrom different streams. Out of whichsynthesiz- ing the diverseorganic moleculesandscreening fortheir biolog- ical activityhas immense role [1]. In the current scenario,focus is mainlyonsyntheticlibraries,structuraldiversity,efficiencyetc.
[2] Inthiscontext, multicomponentreactions (MCRs) havefound greatattentioninthedrugdiscoveryprocess inbuildingdesigned librarieswithstructuraldiversity[3].Presentinterestistodevelop suchnoveldrugcandidatesbyMCRsforpreclinicalstudies.
∗Correspondence Dr. Prashantha Kumar BR Department of Pharmaceutical Chem- istry, JSS College of Pharmacy, Mysuru 570 015, India.
E-mail address: [email protected] (B.P. Kumar) .
PietroBelinelliin1893reportedthecyclocondensationreaction by combining
β
-ketoester, aldehyde andurea/thiourea dissolved in solventethanol using acid catalystwith minimal heating. The obtainedproductwasprecipitatedbycoolingthereactionmixture andidentified asnovel 1,4-dihydropyrimidin-2-one [4]. This one- potMCR’sfocusextendedbyvaryingthebuildingblockstogener- atethepotentmoleculesfordifferentpharmaceuticalapplications.1,4-dihydropyrimidinesareknowntohavevariouspharmacological activities like antiviral [5–7], analgesic [8],antibacterial [9], anti- inflammatory[10],anti-Alzheimer[11],anti-thrombic[12],antihy- pertensive[13] andcalcium channelblockade [14,15] activity. Due tothesewiderangesoftherapeutic properties,pharmaceuticalin- dustryisattractedindevelopingnoveldihydropyrimidines[16].
Manyevidences haverevealed that membersinErbB receptor of tyrosine kinase family plays crucial role in human breast car- cinoma[17].The overexpression ofEpidermalGrowthFactorRe- ceptor(EGFR/ErbB1) [18]andHumanepidermalgrowthfactorre- ceptor(HER2/ErbB2)leadstothegrowthandprogressionoftumor
https://doi.org/10.1016/j.molstruc.2022.134 84 8 0022-2860/© 2022 Elsevier B.V. All rights reserved.
Tyrosinekinaseinhibitors(TKIs)areanoral,well-toleratedcat- egory of small molecules used in medicine to treat a variety of cancers, such as breast, gastro-intestinal stromal tumors,chronic myeloid leukemia,lung, kidney,andpancreatic cancer [21].Ato- tal of three generations of EGFR Tyrosine Kinase inhibitors have been authorized for use in the treatment of cancer by EGFR in- hibition. EGFRfamilyincludesexpressionofEGFRs,namely,HER1, HER2,HER3andHER4.First-generation TKIsincludelapatinib,er- lotinib, gefitinib, and icotinib; second-generation EGFR inhibitors include afatinib, neratinib, and dacomtinib; and third-generation TKIs, including osimertinib,olmutinib andalmonertinib [22]. Pa- tients withcancercanbenefitgreatlyfromEGFRinhibitors.Since, genomic instabilityandtumorheterogeneity aredefining features of tumor biology, resistance tosuch EGFRinhibitorsis inevitable [23].So,inthelightoftheseobservationsthere’sneedfordesign- ing the new moleculeswhich structurallyresembles thetyrosine kinase inhibitors which could overcome the problem of treating thecancerpatients.
Aspartofdrugresearch,Computeraideddrugdesigntoolslike CoMFA (Comparativemolecular field analysis)and CoMSIA(com- parativemolecular similarityindices analysis)helpsingenerating thestructuralactivityrelationshipby3D-QSARstudies[24,25].
Inthiscontextwereportaboutthedesign,synthesis,analysisof novel 1,4-dihydropyrimidines andtheir anticanceractivityagainst breast cancer along withstructural activity relationships via 3D- QSARmodels.
2. Experimental 2.1. Chemistry
Synthetic work wasperformedusing analytical gradesolvents and laboratory gradereagents. These were dried andpurified by followingtheprocedurementionedinthetextbookofpracticalor- ganic chemistry by Vogel. Using ethyl acetate/n-Hexane (4:6) as mobile phase, TLC was performed to know the progress of re- action andproduct purity.Later, purificationof synthesizedcom- poundswasdonebyrecrystallizationandcolumnchromatography.
Throughopencapillarymethod,meltingpoint(in◦C)ofeachprod- uct wasdetermined.IRSpiritShimadzuATRspectrophotometeris used to record the IRspectra ofsynthesized compounds. Spectra of1Hand13C-NMRwasrecordedon400MHzFT-NMRspectrom- eter by taking DMSO-d6 as solvent andtetramethyl silane (TMS) asan internal standard (
δ
ppm).Massspectra were obtainedus-ing API -4000,SciexLC-MS/MS massspectrometerwithelectron channel multiplier detectorandcyanocolumn. Elemental analysis was carriedout for carbon,hydrogen,nitrogen andsulfur (sulfur for only sulfur containing compounds) using an Elementar Vario (EL III Carlo Erba11080). By Catalyst scientific microwave system, microwaveirradiationwasperformedforfewreactionsthatneeds heating.
2.1.1. Synthesisof4-acetoacetanisidide(Compound1)
Synthesized by takingequimolar amount ofethyl acetoacetate andp-methoxyanilineina roundbottomflaskandrefluxedfor2 h [26].Obtained crudesolid waswashed withetherandthen re- crystallizedbyaq.ethanoltogetsolidcrystals.Theformedproduct waslatercharacterizedbytheTLCwithmobilephaseofn-Hexane andethylacetate(8:2).Theobtainedyieldwas48%.
Compound–1: N-(4-methoxyphenyl)-3-oxobutanamide (C11N13
NO3) whiteamorphoussolid, yield: 48%,M.p 115-117°C,Rf = 3.5 (n-Hexane/EtOAc8:2).
Equivalent quantities of 4-acetoacetanisidide (0.01M), substi- tuted aldehyde (0.01M) and excess amount of urea/thiourea (0.015M) was taken in round bottomed flask along with dry ethanolasa solventandp-toluenesulphonicacidasacatalystin smallquantity(50mg).Thisreactionmixturewasstirredfor24– 30hatnormalroomtemperature. Progressofreactionwasmoni- toredbyTLC.Infewreactions,thioureawasobservedtobestillre- mained.Ifthereactionwasincomplete,thenitwasslightlyheated oralternatively itis microwaved for15-20 minsat 500Wpower.
Oncethereactiongetscompleted,theformedproductsweretaken forthe workup by washing oncewith 5% NaOHandtwice with 30ml of water. Through filtration, final solid products were col- lected. Laterthe products are recrystallized withaq. ethanoland aresubjectedforcolumnchromatographyusingsolventsystemn- Hexane andethyl acetate (10:3) forits purification.The obtained yields areseeming tobe goodandrangingfrom67to99%.Refer thesupplementarymaterialfortheanalyticalspectra.
Compound–2: 4-(2-chlorophenyl)-N-(4-methoxyphenyl)-6- methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide]
(C19H18ClN3O3) white amorphous solid, yield: 84%, m.p: 184 – 186°C,Rf = 0.35 (ethylacetate/n-hexane 2:8), IR(cm−1): 3420.17 (N–H), 3261.46 (N–H), 3115.62 (ArC–H), 2963.52 (aliph. C-H), 1705.80 (C=O), 1667.19 (C=O), 1514.20 (ArC=C), 1172.47 (C–O), 660.59 (C–Cl), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 1.97 (s, 3H, CH3); 3.64 (s, 3H, CH3); 5.72 (s, 1H, CH); 6.77 (d, 2H, ArH3JHH = 8.00Hz); 7.20 (d, 1H, ArH 3JHH = 8.00Hz); 7.23 (m, 1H, ArH);7.35(m,1H,ArH);7.32 (d,1H,ArH3JHH =8.00Hz);7.41(d, 2H,ArH3JHH =8.00Hz); 7.46 (s, 1H,NH); 8.73(s,1H, NH);9.52 (s,1H,NH),13C NMR(
δ
ppm, 400 MHz, DMSO-d6):17.34 (CH3);53.29(CH);55.64(OCH3);105.22(ArC);114.16(ArC);121.47(ArC);
128.20 (ArC); 129.71 (ArC); 129.88 (ArC); 129.95 (ArC); 131.94 (ArC); 132.80 (ArC); 138.34 (ArC); 141.62 (ArC); 152.79 (C=O);
155.63(ArC); 165.06(C=O).LC-MSMS(m/z):[PeakFound (M+23):
410.1(calculated(M+23):410.8)]Fragmentpeak:218.0.
Anal. Calcd. for C19H18ClN3O2S: C, 58.83; H, 4.68; N, 10.83;
Found:C,58.99;H,4.57;N,10.71
Compound–3: N,4-bis(4-methoxyphenyl)-6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide] (C20H21N3O4) white amorphous solid, yield: 78%, m.p: 197 – 199°C, Rf = 0.5 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3232.86 (N–H), 3267.18 (N–
H), 3117.05 (ArC–H), 2835.37(aliph. C-H), 1711.52 (C=O),1622.87 (C=O), 1509.91 (ArC=C), 1173.90 (C–O), 1H NMR (
δ
ppm, 400MHz, DMSO-d6): 2.02 (s, 3H, CH3); 3.68 (s, 6H, OCH3); 5.33 (s, 1H, CH);6.81 (d, 2H, ArH 3JHH =8.00Hz); 6.86(d, 2H,ArH 3JHH
=8.00Hz); 7.17 (d, 2H,ArH 3JHH =8.00Hz); 7.43 (d, 2H, ArH3JHH
=8.00Hz); 7.52(s,1H,NH);8.67(s,1H,NH);9.41(s,1H,NH),13C NMR(
δ
ppm,400MHz,DMSO-d6):17.52(CH3);55.01(CH);55.58 (OCH3); 55.65 (OCH3); 106.20 (ArC); 114.14 (ArC); 114.28 (ArC);121.61(ArC);128.03(ArC);132.91(ArC);137.01(ArC);138.23(ArC);
153.11(C=O);155.62(ArC);159.01(ArC);165.45(C=O),LC-MSMS (m/z):[Peak Found (M−1):366.3 (calculated (M−1): 366.4)] Frag- mentpeaks:339.0,352.8,393.1.
Anal.Calcd.forC20H21N3O4:C,65.38;H,5.76;N,11.44;Found:
C,65.55;H,5.62;N,11.57
Compound–4: 4-(4-bromophenyl)-N-(4-methoxyphenyl)-6-me thyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide]
(C19H18BrN3O3) white amorphous solid, yield: 78%, m.p: 185 – 187°C,Rf=0.5(ethylacetate/n-hexane 2:8),IR(cm−1):3337.24 (N–H), 3258.60 (N– H), 3101.32 (ArC–H), 2952.62 (aliph. C-H), 1712.95 (C=O), 1671.48 (C=O), 1515.63 (ArC=C), 1009.47 (C–O), 646.29 (C–Br), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 1.99 (s, 3H, CH3); 3.66 (s, 3H, CH3); 5.32 (s, 1H, CH); 6.78 (d, 2H, ArH3JHH= 8.00Hz);7.20(d,2H,ArH3JHH=8.00Hz); 7.38(d,2H,ArH
3JHH=8.00Hz);7.44(d,2H,ArH3JHH =8.00Hz);7.80(s,1H,NH);
8.56 (s, 1H, NH); 9.30 (s,1H, NH), 13C NMR (
δ
ppm, 400 MHz,DMSO-d6): 16.54 (CH3);55.23(CH); 55.64(OCH3); 105.63(ArC);
114.33 (ArC); 121.31 (ArC); 122.20 (ArC); 131.34 (ArC); 138.42 (ArC); 139.20 (ArC); 141.23 (ArC); 145.60 (ArC); 152.30 (C=O);
156.60 (ArC);165.01 (C=O). LC-MSMS(m/z): [PeakFound (M+2):
418.1(calculated(M+2):418.2)].
Anal. Calcd. for C19H18BrN3O3: C, 54.82; H, 4.36; N, 10.09;
Found:C,54.96;H,4.44;N,10.21.
Compound–5:N-(4-methoxyphenyl)-6-methyl-2-oxo-4-styryl-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C21H21N3O3) yellow amorphous solid, yield: 68%, m.p: 192 – 194°C, Rf = 0.75 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3328.66 (N–H), 3208.12 (N–H), 3079.87 (ArC–H), 2965.48 (aliph. C-H), 1708.66 (C=O), 1662.90 (C=O), 1614.29 (aliph. C=C), 1508.48 (ArC=C), 1178.19 (C–O), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 2.04 (s, 3H, CH3); 3.86 (s, 3H,OCH3);4.84(s,1H,CH);6.87(d,2H,ArH3JHH=8.00Hz);6.96 (s,1H,CH = CH);6.99(s,1H,CH=CH);7.27(s,1H,NH); 7.30 (s, 1H, ArH); 7.34 (d, 2H, ArH3JHH =4.00Hz); 7.48 (d, 2H,ArH 3JHH=8.00Hz)7.48(s,1H,NH); 7.56 (d,2H,ArH3JHH =4.00Hz);10.12 (s,1H,NH),13CNMR (
δ
ppm,400 MHz, DMSO-d6): 26.97(CH3);55.72 (CH, OCH3); 114.43 (ArC); 121.50 (ArC); 124.36 (CH=CH);
128.03 (ArC); 129.63 (ArC); 130.25 (ArC); 132.59 (ArC); 136.01 (ArC); 138.74 (ArC); 141.47 (CH); 143.67 (C=O); 156.03 (ArC, OCH3);164.55 (C=O).LC-MSMS(m/z): [PeakFound (M−1):362.2 (calculated(M−1):362.4)]Fragmentpeak:212.9.
Anal. Calcd. for C21H21N3O3: C, 69.41; H, 5.82; N, 11.56; O, 13.21;Found:C,69.59;H,5.91;N,11.71.
Compound–6:N-(4-methoxyphenyl)-6-methyl-4-(2-nitrophenyl )-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H18N4O5) cream amorphous solid, yield: 77%, m.p: 193 – 195°C, Rf = 0.7 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3478.80 (N–H), 3297.21 (N– H), 3107.68 (ArC–H), 2863.42 (aliph. C-H), 1668.62(C=O),1655.75(C=O),1591.41(ArC=C),1518.49(R–NO2), 1129.57(C–O),1HNMR(
δ
ppm,400 mHz,DMSO-d6):1.01 (s,3H, CH3);3.35 (m,3H,OCH3);5.41(s,1H,CH);6.83(d,2H,ArH3JHH=8.00Hz); 7.08 (d, 1H,ArH 3JHH =8.00Hz); 7.47 (t, 2H,ArH 3JHH
=8.00Hz); 7.60 (t, 1H,ArH 3JHH =8.00Hz); 7.66 (d, 2H,ArH 3JHH
=8.00Hz);7.72(s,1H,NH);7.82(d,1H,ArH3JHH =8.00Hz);8.5(s, 1H,NH);11.05(s,1H,NH),13CNMR(
δ
ppm,400MHz,DMSO-d6):19.10(CH3);56.55(CH);56.67(OCH3);124.72(ArC);124.79(ArC);
128.98 (ArC); 129.08 (ArC); 129.21 (ArC); 133.20 (ArC); 133.21 (ArC); 148.62 (ArC); 157.92 (C=O). LC-MSMS (m/z): [Peak Found (M+2): 384.9 (calculated (M+2): 384.3)] Fragment peaks: 265.1, 295.4.
Anal.Calcd.forC19H18N4O5:C,59.68;H,4.75;N,14.65;Found:
C,59.79;H,4.92;N,14.77.
Compound–7: 4-(3,4-dimethoxyphenyl)-N-(4-methoxyphenyl)- 6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C21H23N3O5) white amorphous solid, yield: 75%, m.p: 178 – 180°C,Rf= 0.65(ethylacetate/n-hexane2:8), IR(cm−1):3463.20 (N–H), 3279.12 (N–H), 3150.15 (ArC–H), 2965.48 (aliph. C-H), 1712.95 (C=O), 1677.20(C=O), 1514.20(ArC=C), 1138.15, 1089.54, 1018.04 (C–O), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 1.98 (s, 3H, CH3); 3.62 (s, 3H, OCH3); 3.65 (d, 3H, OCH3); 3.65 (d, 3H, OCH3);5.30(s,1H,CH); 6.77 (s,1H,ArH); 6.81(d,2H, ArH3JHH=8.00Hz); 6.85(s, 1H,ArH); 6.86 (s,1H,ArH); 6.91 (s, 1H,NH);
7.42 (d, 2H,ArH 3JHH =8Hz); 8.60(s, 1H,NH); 9.38 (s,1H, NH),
13C NMR (
δ
ppm, 400 MHz, DMSO-d6): 17.51 (CH3); 55.21(CH);55.66 (OCH3); 55.88 (OCH3); 56.03 (OCH3); 106.07 (ArC); 110.81 (ArC);112.18(ArC);114.17(ArC);118.60(ArC);121.66(ArC);137.25 (ArC); 138.17 (ArC); 148.60 (ArC); 149.08 (ArC); 153.18 (C=O);
155.67 (ArC);165.57(C=O).LC-MSMS(m/z):[PeakFound(M+23):
420.3(calculated(M+23):420.4)]Fragmentpeaks:377.2.
Anal.Calcd.forC21H23N3O5:C,63.47;H,5.83;N,10.57;Found:
C,63.63;H,5.72;N,10.71.
Compound–8: 4-(3-hydroxyphenyl)-N-(4-methoxyphenyl)- 6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide]
(C19H19N3O4) cream amorphous solid, yield: 80%, m.p: 198 – 200°C, Rf = 0.7(ethyl acetate/n-hexane 2:8), IR (cm−1): 3245.73 (O–H),2953.52(aliph.C-H),1701.02(C=O),1630.02(C=O),1514.20 (ArC=C), 1148.16 (C–O), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6):1.99(s,3H,CH3);3.64(s,3H,CH3);5.07(s,1H,CH);6.06(d,2H, ArH3JHH = 4.00Hz); 6.18(d,2H,ArH3JHH =7.00Hz); 6.36(s,1H, ArH); 6.48 (s, 1H, OH); 6.70 (t, 1H, ArH 3JHH = 7.00 Hz); 6.75 (d, 2H, ArH 3JHH = 8.00Hz); 6.93 (s, 1H, NH); 7.42 (d, 2H, ArH
3JHH = 8.00Hz); 7.54 (s, 1H, NH), 13C NMR (
δ
ppm, 400 MHz,DMSO-d6): 17.61 (CH3); 55.76 (CH); 40.26 (OCH3); 106.63 (ArC);
114.20(ArC);112.18(ArC);116.21(ArC);117.94(ArC);121.74(ArC);
128.96 (ArC); 133.21 (ArC); 138.20 (ArC); 145.22 (ArC); 153.81 (C=O);155.62(C-OH);165.91(C=O).LC-MSMS(m/z):[PeakFound (M+2): 355.2 (calculated (M+2): 355.3)] Fragment peaks: 168.2, 191.0,206.1,231.8,314.2.
Anal.Calcd.forC19H19N3O4:C,64.58;H,5.42;N,11.89;Found:
C,64.69;H,5.58;N,11.78.
Compound–9: N-(4-methoxyphenyl)-6-methyl-2-oxo-4-(p- tolyl)-1,2,3,4-tetrahydropyrimidine-5-carboxamide (C20H21N3O3) white amorphous solid, yield: 85%, m.p: 185 – 187°C, Rf = 0.5 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3398.73 (N–H), 3281.48 (N– H), 3150.20 (ArC–H), 2930.64 (aliph. C-H), 1708.66 (C=O), 1668.62 (C=O), 1511.34 (ArC=C), 1035.20 (C–O), 823.59 (p C–H),
1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 1.97 (s, 3H, CH3); 2.13 (s, 3H, CH3); 3.64 (s, 3H, CH3); 5.31 (s, 1H, CH); 6.76 (d, 2H, ArH3JHH = 8.00Hz);7.09 (d, 2H,ArH3JHH =8.00Hz); 7.4(d,2H, ArH3JHH = 8.00Hz); 7.06(s,1H,ArH); 7.12 (s,1H,ArH); 7.48(s, 1H, NH); 8.62 (s, 1H, NH); 9.38 (s, 1H, NH), 13C NMR (δ
ppm,400 MHz, DMSO-d6): 17.51 (CH3);21.17 (CH3);55.32(CH); 55.66 (OCH3); 106.15 (ArC); 114.15 (ArC); 121.62 (ArC); 126.71 (ArC);
129.49 (ArC); 132.89 (ArC); 136.95 (ArC); 138.18 (ArC); 141.94 (ArC);153.19(C=O);155.64(ArC);165.46(C=O),LC-MSMS(m/z):
[Peak Found (M+1): 352.2 (calculated (M+1): 352.4)] Fragment peaks:353.1,354.0.
Anal.Calcd.forC20H21N3O3:C,68.36;H,6.02;N,11.96;Found:
C,68.50;H,6.18;N,11.86.
Compound–10: 4-(3-ethoxy-4-hydroxyphenyl)-N-(4- methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine- 5-carboxamide (C21H23N3O5) cream amorphous solid, yield: 73%, m.p: 196 – 198°C, Rf = 0.75 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3401.20 (N–H), 3348.21 (N–H), 3268.40 (O–H), 3162.21 (ArC–H), 2998.64 (aliph. C-H), 1672.91 (C=O), 1630.02 (C=O), 1511.34 (ArC=C), 1279.71 (C–O–C), 1033.77 (C–O), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 1.22(s, 3H, CH3); 1.97 (s, 3H,CH3);
3.65(s,3H,CH3);3.85(m,1H,aliph.CH2);5.25(s,1H,CH);6.65 (d,2H,ArH3JHH = 12.00Hz);6.62(s,1H,ArH); 6.75(m,3H,ArH
3JHH = 12.00Hz); 7.38 (d, 2H, ArH 3JHH = 8.00Hz); 6.79 (s, 1H, NH);8.58(s,1H,NH);8.82(s,1H,NH);9.35(s,1H,OH),13CNMR (
δ
ppm, 400 MHz, DMSO-d6): 15.24 (CH3); 17.49 (CH3); 55.26 (CH); 55.65 (OCH3);64.36 (aliph. C); 106.27 (ArC); 112.64 (ArC);114.13 (ArC); 115.85 (ArC); 119.08 (ArC); 121.64 (ArC); 132.88 (ArC); 135.75 (ArC); 137.90 (ArC); 146.64 (ArC); 146.93 (ArC);
153.17(C=O); 155.64(ArC);165.40(C=O), LC-MSMS(m/z):[Peak Found (M+1): 398.4 (calculated (M+1): 398.4)] Fragment peaks:
399.2,400.2.
Anal.Calcd.forC21H23N3O5:C,63.47;H,5.83;N,10.57;Found:
C,63.62;H,5.98;N,10.72.
Compound–11: N-(4-methoxyphenyl)-6-methyl-2-oxo-4- (thiophen-2-yl)-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C17H17N3O3S) white amorphous solid, yield: 72%, m.p: 199 – 200°C, Rf = 0.7 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3501.20 (N–H), 3348.21 (N–H), 3182.10 (ArC–H), 2997.85 (aliph. C-H), 1672.91 (C=O), 1630.02 (C=O), 1511.34 (ArC=C), 1095.26 (C–O),
1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 2.01 (s, 3H, CH3); 3.66S. No Compound IC 50 Structural Activity Relationships
1. 14 10.5 Vanillin substitution at 4 thposition of dihydropyrimidine exhibit less IC 50value, which indicates the more potent cytotoxicity.
2. 7 12 Urea derivative of dihydropyrimidine with Veratraldehyde substitution shows good IC 50value indicates good cytotoxicity.
3. 5 12.5 Cinnamaldehyde at 4 thposition of dihydropyrimidine ring has good cytotoxicity with good IC 50
value.
4. 8 40.5 3-Hydroxy benzaldehyde substitution shows moderate IC 50value, which is having less cytotoxicity.
5. 30 62.5 Dihydropyrimidine of benzaldehyde derivative shows more inhibitory concentration with low cytotoxicity.
6. 22 81 Dihydropyrimidine of 3-Hydroxy benzaldehyde shows very high IC 50value with poor cytotoxicity. Urea derivatives is more potent than the thiourea derivatives.
(s, 3H,CH3);5.62 (s,1H, CH);6.81 (d, 2H, ArH3JHH = 8.00Hz);
6.88 (d, 2H,ArH3JHH = 8.00Hz); 7.34 (m,1H, ArH); 7.44(d, 2H, ArH 3JHH = 8.00Hz); 7.76 (s,1H, NH); 8.80 (s,1H, NH); 9.42 (s, 1H, NH), 13C NMR (
δ
ppm, 400 MHz, DMSO-d6): 17.63 (CH3);51.08(CH);55.66(OCH3);105.95(ArC);114.16(ArC);121.84(ArC);
124.06 (ArC); 125.47 (ArC); 127.23 (ArC); 132.87 (ArC); 139.48 (ArC); 149.26 (ArC); 153.05 (C=O); 155.70 (ArC); 165.05 (C=O), LC-MSMS (m/z): [Peak Found (M+1): 344.2 (calculated (M+1):
344.4)]Fragmentpeaks:345.1,346.1.
Anal. Calcd. for C17H17N3O3S: C, 59.46; H, 4.99; N, 12.24; S, 9.34;Found:C,59.63;H,5.12;N,12.36;S,9.52.
Compound–12: (E)-4-(4-(dimethylamino)styryl)-N-(4- methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine- 5-carboxamide (C23H26N4O3) dark red amorphous solid, yield:
82%, m.p: 191 – 192°C, Rf = 0.65 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3388.72 (N–H), 3151.50(ArC–H), 2980.52 (aliph. C-H), 1671.48 (aliph. C=C), 1601.42 (C=O), 1501.25 (ArC=C), 1126.71 (C–O), 1038.06 (C–N), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6):2.46 (s, 3H, CH3); 2.64 (s, 6H, 2CH3); 3.69 (s, 3H, CH3); 4.81 (s, 1H, CH); 5.72 (d, 1H, CH 3JHH = 12.00Hz); 7.33 (d, 1H, CH
3JHH = 12.00Hz);5.81(s,1H,ArH); 6.15(s,1H,ArH);6.61(d, 2H, ArH3JHH =8.00Hz);6.87(d,2H,ArH3JHH =8.00Hz);7.09 (s,1H, ArH); 7.51 (s,1H, ArH); 7.61 (s, 1H,NH); 9.51 (s, 1H,NH); 9.79 (s,1H,NH),13CNMR (
δ
ppm,400 MHz,DMSO-d6): 22.23(CH3);50.53 (2CH3); 55.71 (OCH3); 100.01 (ArC); 112.27 (ArC); 122.27 (ArC); 121.42 (ArC), LC-MSMS (m/z): [Peak Found (M+1): 407.0 (Calculated(M+1):407.4)]Fragmentpeaks:407.0.
Anal.Calcd.forC23H26N4O3:C,67.96;H,6.45;N,13.78;Found:
C,67.81;H,6.56;N,13.93.
Compound–13: 4-(4-(benzyloxy)-3-methoxyphenyl)-N-(4- methoxyphenyl)-6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine- 5-carboxamide (C27H27N3O5) white amorphous solid, yield: 75%, m.p: 174 – 176°C, Rf = 0.75 (ethyl acetate/n-hexane 2:8), IR (cm−1):3405.05 (N–H), 3288.63(N–H), 3108.47 (ArC–H), 2934.03 (aliph. C-H), 1710.09 (C=O), 1671.48 (C=O), 1502.37 (ArC=C), 1262.55 (C–O), 1133.86 (C–O), 1023.76 (C–O), 1H NMR (
δ
ppm,400 mHz, DMSO-d6): 1.99 (s, 3H, CH3); 3.65 (s, 3H, CH3); 3.79 (s, 3H, CH3); 4.99 (s, 1H, CH); 5.17 (s, 2H, CH2); 6.77 (d, 1H, ArH 3JHH = 8.00Hz); 6.86 (d, 1H, ArH 3JHH = 8.00Hz); 6.93 (d, 2H, ArH 3JHH = 8.00Hz); 7.23 (d, 2H, ArH 3JHH = 8.00Hz); 7.27 (d, 2H, ArH 3JHH = 8.00Hz); 7.33 (m, 1H,ArH 3JHH = 12.00Hz);
7.42 (d, 2H, ArH 3JHH = 8.00Hz); 7.50 (s, 1H, NH); 9.42 (s, 1H, NH); 9.80 (s, 1H, NH), 13C NMR (
δ
ppm, 400 MHz, DMSO-d6):17.52 (CH3); 55.23 (CH); 55.64 (OCH3); 55.94 (OCH3); 70.37 (CH2); 106.06 (ArC); 110.10 (ArC); 111.03 (ArC); 114.16 (ArC);
118.55 (ArC); 121.68 (ArC); 126.52 (ArC); 128.30 (ArC); 128.35 (ArC); 128.56 (ArC); 128.93 (ArC); 129.05 (ArC); 136.80 (ArC);
137.61 (ArC); 147.56 (ArC); 149.41 (ArC); 149.88 (ArC); 153.21 (C=O); 155.67 (ArC); 165.59(C=O),LC-MSMS(m/z): [PeakFound
(M+1): 474.5 (Calculated (M+1): 474.5)] Fragment peaks: 473.5, 475.3.
Anal.Calcd.forC27H27N3O5:C,68.49;H,5.75;N,8.87;Found:
C,68.57;H,5.89;N,8.98.
Compound–14: 4-(4-hydroxy-3-methoxyphenyl)-N-(4- methoxyphenyl)-6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine- 5-carboxamide (C20H21N3O5) cream amorphous solid, yield: 75%, m.p:183– 186°C,Rf=0.5(ethylacetate/n-hexane2:8),IR(cm−1):
3408.65 (O–H), 3358.62 (N–H), 3230.01 (N–H), 3101.32 (ArC–H), 2955.48 (aliph. C-H), 1693.48 (C=O), 1628.59 (C=O), 1501.34 (ArC=C), 1095.26 (C–O), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6):1.97(s,3H,CH3);3.13(s,3H,CH3);3.63(s,3H,CH3);5.26(s,1H, CH);6.65(s,1H,ArH); 6.78(d, 1H,ArH 3JHH = 8.00Hz); 7.42 (d, 2H, ArH 3JHH = 8.00Hz); 6.85 (d, 1H, ArH 3JHH = 8.00Hz); 7.01 (d, 2H, ArH 3JHH = 8.00Hz); 7.36 (s, 1H, NH); 8.58 (s, 1H, NH);
9.36 (s,1H, NH); 9.47 (s, 1H, OH),13C NMR (
δ
ppm, 400 MHz,DMSO-d6):17.49 (CH3);39.64(CH); 55.64(OCH3);56.00(OCH3);
106.22(ArC);111.20(ArC);114.15(ArC);115.74(ArC);118.99(ArC);
121.68 (ArC); 132.85 (ArC); 135.75 (ArC); 137.91 (ArC); 146.32 (C-OH); 147.86 (ArC); 153.16 (C=O); 155.65 (ArC); 165.62 (C=O).
LC-MSMS (m/z): [Peak Found (M+1): 384.3 (calculated (M+1):
384.4)]Fragmentpeaks:137.2,218.0,260.2.
Anal.Calcd.forC20H21N3O5:C,62.65;H,5.52;N,10.96;Found:
C,62.77;H,5.70;N,11.08.
Compound–15: 4-(2,6-dichlorophenyl)-N-(4-methoxyphenyl)- 6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H17Cl2N3O3) white amorphous solid, yield: 74%, m.p: 177 – 179°C, Rf = 0.7 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3314.37 (N–H), 2998.67 (aliph. C-H), 1648.60 (C=O), 1501.38 (ArC=C), 1090.97 (C–O), 686.68 (C–Cl), 580.51 (C–Cl), 1H NMR (
δ
ppm,400 mHz, DMSO-d6): 1.03 (s, 3H, CH3); 3.62 (s, 3H, CH3); 4.31 (s, 1H, CH); 5.64 (d, 2H, ArH 3JHH = 8.00Hz); 7.40 (d, 2H, ArH
3JHH=8.00Hz);7.06(d,2H,ArH3JHH =8.00Hz);6.63(s,1H,NH);
7.62 (s,1H,NH);7.72 (s,1H,NH); 6.76(m,1H,ArH),13CNMR(
δ
ppm,400 MHz,DMSO-d6):15.2(CH3);56.81(CH);56.97(OCH3);
102.71 (ArC); 115.20 (ArC); 129.82 (ArC); 130.26 (ArC); 130.34 (ArC); 134.03 (ArC); 157.36 (ArC). LC-MSMS (m/z): [Peak Found (M−2): 404.0 (calculated (M−2): 404.2)] Fragment peaks: 255.7, 256.7,258.1.
Anal. Calcd. for C19H17Cl2N3O3: C, 56.17; H, 4.22; N, 10.34;
Found:C,56.29;H,4.38;N,10.48.
Compound–16: N-(4-methoxyphenyl)-6-methyl-2-oxo-4- phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxamide (C19H19N3O3) white amorphoussolid, yield: 76%, m.p: 199 – 200°C, Rf = 0.65 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3736.71 (N–H), 3272.90 (N–H), 3115.62 (ArC–H), 2330.64 (aliph. C-H), 1708.66 (C=O), 1678.63(C=O),1514.20(ArC=C),1093.83(C–O), 1H NMR(
δ
ppm,400 mHz, DMSO-d6): 1.98 (s, 3H, CH3); 3.64 (s, 3H, CH3); 5.35 (s,1H,CH); 6.78(d, 2H,ArH3JHH =8.00Hz); 7.23 (m,1H, ArH);
Table 2
Training set of synthesized 1,4-dihydropyrimdinones and cytotoxicity against MCF-7 breast cancer cells and Vero cells.
CPD NO. STRUCTURE IC 50μg/ml (MCF-7) IC 50μg/ml ( Vero ) -Exp lnMCyt -Pred lnMCyt
2. 36.5 125 2.321 2.405
3. 28 138.5 2.574 2.822
4. 18 97.5 3.140 3.094
5. 12.5 110.5 3.369 3.527
7. 12 88 3.500 3.144
( continued on next page )
8. 40.5 147 2.166 2.042
9. 21 104.5 2.817 2.801
10. 24.5 111 2.786 3.336
11. 30 127.5 2.437 2.387
13. 27 132 2.864 2.868
( continued on next page )
Table 2 ( continued )
CPD NO. STRUCTURE IC 50μg/ml (MCF-7) IC 50μg/ml ( Vero ) -Exp lnMCyt -Pred lnMCyt
14. 10.5 86.5 3.597 3.149
16. 38 139 2.183 2.349
18. 31 142 2.484 2.556
19. 27.5 118.5 2.717 2.549
21. 21.5 111 2.956 2.739
( continued on next page )
22. 81 196 1.517 1.516
23. 23.5 115.5 2.781 2.959
24. 37 143 2.295 2.324
25. 31 151 2.635 2.442
( continued on next page )
7.28 (d,4H,ArH3JHH =8.00Hz);7.40 (d,2H,ArH3JHH =8.00Hz);
7.55 (s,1H,NH); 9.42(s, 1H,NH); 9.54(s, 1H,NH), 13C NMR (
δ
ppm,400MHz,DMSO-d6):17.53(CH3);55.58(CH);55.65(OCH3);
106.05 (ArC); 114.16 (ArC); 121.68 (ArC); 126.77 (ArC); 127.84 (ArC); 129.00 (ArC); 132.85 (ArC); 138.37 (ArC); 144.85 (ArC);
153.23(C=O); 155.67(ArC); 165.45(C=O).LC-MSMS(m/z):[Peak Found (M+1): 338.1 (calculated (M+1): 338.3)] Fragment peaks:
212.1,260.1,295.2,321.0.
Anal.Calcd.forC19H19N3O3:C,67.64;H,5.68;N,12.46;Found:
C,67.78;H,5.82;N,12.63.
Compound–17: 4-(3,4-dichlorophenyl)-N-(4-methoxyphenyl)- 6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H17Cl2N3O3) white amorphous solid, yield: 86%, m.p: 196 – 199°C,Rf = 0.65(ethylacetate/n-hexane2:8), IR(cm−1):3275.76 (N–H), 3149.71 (ArC–H), 2985.69 (aliph. C-H), 1712.95 (C=O), 1671.48 (C=O), 1501.34 (ArC=C), 1029.48 (C–O) 770.68 (C–Cl),
Table 2 ( continued )
CPD NO. STRUCTURE IC 50μg/ml (MCF-7) IC 50μg/ml ( Vero ) -Exp lnMCyt -Pred lnMCyt
26. 38 138 2.555 2.602
28. 55 189 1.953 1.930
29. 48 152 2.013 2.065
30. 62.5 164 1.732 2.039
( continued on next page )
670.59 (C–Cl), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 2.00 (s, 3H, CH3); 3.65 (s, 3H, CH3); 5.32 (s, 1H, CH); 6.79 (d, 2H, ArH3JHH =8.00Hz);7.21(d,1H,ArH3JHH =8.00Hz);7.37(d,1H,ArH
3JHH=8.00Hz);7.43(s,1H,ArH);7.57(d,2H,ArH3JHH=8.00Hz);
7.64 (s,1H,NH); 8.80(s,1H,NH); 9.47 (s, 1H,NH), 13C NMR (
δ
ppm,400MHz,DMSO-d6):17.62(CH3);54.71(CH);55.66(OCH3);
105.03 (ArC); 114.21 (ArC); 121.80 (ArC); 127.26 (ArC); 128.88 (ArC); 130.40 (ArC); 131.33 (ArC); 131.51 (ArC); 132.61 (ArC);
139.22 (ArC); 145.73 (ArC); 152.89 (C=O); 155.80 (ArC); 165.20 (C=O). LC-MSMS (m/z): [Peak Found (M−1): 405.2 (calculated (M−1):405.2)]Fragmentpeaks:259.0,321.0,362.0.
Anal. Calcd. for C19H17Cl2N3O3: C, 56.17; H, 4.22; N, 10.34;
Found:C,56.29;H,4.38;N,10.50.
Compound–18: 4-(4-chlorophenyl)-N-(4-methoxyphenyl)- 6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H18ClN3O3) white amorphous solid, yield: 81%, m.p: 193 –
31. 39 175 2.361 2.591
32. 16.5 87.5 3.186 2.692
33. 53 158.5 1.990 2.193
34. 42.5 174.5 2.319 2.129
195°C, Rf = 0.3 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3408.73 (N–H), 3100.01 (ArC–H), 2901.11 (aliph. C-H), 1668.62 (C=O), 1620.01 (C=O), 1514.20 (ArC=C), 1086.68 (C– O), 770.68 (C–Cl),
1HNMR(
δ
ppm, 400mHz,DMSO-d6):2.03(s,3H,CH3);3.69(s, 3H,CH3);5.37 (s,1H,CH);6.81(d,2H,ArH3JHH = 8.00Hz);7.27 (d, 2H,ArH 3JHH = 8.00Hz); 7.39 (m, 4H,ArH); 7.59 (s,1H,NH);8.72 (s,1H, NH); 9.43(s, 1H,NH). LC-MSMS (m/z):[Peak Found (M+23): 394.1 (calculated (M+23): 394.8)] Fragment peaks: 271.3, 350.9.
Anal. Calcd. for C19H18ClN3O3: C, 61.38; H, 4.88; N, 11.30;
Found:C,61.55;H,4.98;N,11.52.
Compound–19: 4-(3-bromophenyl)-N-(4-methoxyphenyl)- 6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H18BrN3O3) white amorphous solid, yield: 78%, m.p: 189 – 190°C, Rf = 0.5(ethyl acetate/n-hexane 2:8), IR (cm−1): 3322.94 (N–H), 2999.09 (aliph. C-H), 1636.48 (C=O), 1512.48 (ArC=C), 1241.10(C–O), 580.51(C–Br),1H NMR(
δ
ppm, 400 mHz,DMSO-d6): 2.04 (s, 3H, CH3); 3.70 (s, 3H, CH3); 5.37 (s,1H, CH); 6.82 (d, 2H,ArH 3JHH = 8.00Hz); 7.30 (m, 2H,ArH); 7.42 (d, 4H,ArH
3JHH = 8.00 Hz); 7.62 (s, 1H, NH); 8.76 (s, 1H, NH); 9.46 (s, 1H, NH). LC-MSMS(m/z): [Peak Found (M+23): 440.0(calculated (M+23):439.2)].
Table 3
Test set of synthesized 1,4-dihydropyrimdinones and cytotoxicity against MCF-7 breast cancer cells and Vero cells.
CPD NO. STRUCTURE IC50 μg/ml (MCF-7) IC50 μg/ml ( Vero ) -Exp lnMCyt -Pred lnMCyt
6. 25 118 2.727 2.565
12. 44.5 147.5 2.212 2.322
15. 25.5 117 2.768 2.624
17. 34 155.5 2.480 2.637
20. 24 103 2.826 2.899
( continued on next page )
27. 41.5 162.5 2.223 2.468
Anal. Calcd. for C19H18BrN3O3: C, 54.82; H, 4.36; N, 10.09;
Found:C,54.98;H,4.58;N,10.33.
Compound–20: N-(4-methoxyphenyl)-6-methyl-2-oxo-4- (4-(trifluoromethyl)phenyl)-1, 2, 3, 4-tetrahydropyrimidine-5- carboxamide (C20H18F3N3O3) white amorphous solid, yield: 79%, m.p: 178 – 179°C, Rf = 0.65 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3275.76 (N–H), 3149.62 (ArC–H), 1667.19 (C=O), 1712.95 (C=O), 1511.34(ArC=C), 1321.18(C–F),1246.82(C–O), 1HNMR (
δ
ppm, 400 mHz, DMSO-d6): 2.04 (s,3H, CH3);3.69 (s,3H, CH3);
5.58(s,1H,CH);6.84(d,2H,ArH3JHH =8.00Hz);7.47(d,2H,ArH
3JHH =8.00Hz);7.51(d,2H,ArH3JHH =8.00Hz);7.57(d,2H,ArH
3JHH = 8.00Hz); 7.74 (d, 1H, NH); 8.78(s, 1H, NH); 9.48 (s, 1H, NH).LC-MSMS(m/z):[PeakFound(M−2):404.9(calculated(M−2):
404.3)]Fragmentpeaks:259.1,321.1,362.0.
Anal. Calcd. for C20H18F3N3O3: C, 59.26; H, 4.48; N, 10.37;
Found:C,59.32;H,4.63;N,10.58.
Compound–21: 4-(3,4-dimethoxyphenyl)-N- (4-methoxyphenyl)-6-methyl-2-thioxo-1, 2, 3, 4- tetrahydropyrimidine-5-carboxamide (C21H23N3O4S) white amor- phous solid, yield: 75%, m.p: 195 – 196°C, Rf = 0.25 (ethyl acetate/n-hexane2:8),IR(cm−1):3292.92(N–H),3189.97(ArC–H), 3000.00 (aliph. C-H), 1680.06 (C=O), 1501.58 (ArC=C), 1484.17 (C=S),1239.67(C–O),1HNMR(
δ
ppm,400 mHz,DMSO-d6):1.12 (s,3H,OCH3);2.01(s,3H,CH3);3.63(s,3H,OCH3); 3.66(d,3H, OCH3);5.31(s,1H,CH);7.42 (d,2H,ArH3JHH =8.00Hz);6.87(d, 2H, ArH 3JHH = 8.00Hz); 6.75(d, 1H, ArH3JHH = 8.00Hz); 6.80 (s,1H, ArH); 6.67 (d, 1H, ArH3JHH = 8.00Hz); 9.32 (s,1H, NH);9.57 (s, 1H, NH); 9.90 (s, 1H,NH), 13C NMR (
δ
ppm, 400 MHz,DMSO-d6):16.97(CH3);55.23(CH3);55.66(OCH3);55.87(OCH3);
56.03 (OCH3); 107.90 (ArC); 110.82 (ArC); 112.23 (ArC); 114.22 (ArC); 118.82 (ArC); 121.75 (ArC); 132.58 (ArC); 135.38 (ArC);
135.92 (ArC); 148.84 (ArC); 149.11 (ArC); 155.84 (ArC); 165.20
Fig. 1. Rational designed structure of novel dihydropyrimidines by the scaffold hybridization technique with EFGR inhibitors (a) Gefitinib, (b) Afatinib; R indicates different substitutions.
Fig. 2. Alignment of training set molecules by field fit method.
(C=O); 174.42 (C=S), LC-MSMS (m/z): [Peak Found (M+1): 414.6 (Calculated(M+1):414.4)].
Anal.Calcd.forC21H23N3O4S:C,61.00;H,5.61;N,10.16;S,7.75;
Found:C,61.13;H,5.77;N,10.30;S,7.89.
Compound–22: 4-(3-hydroxyphenyl)-N-(4-methoxyphenyl)-6- methyl-2-thioxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H19N3O3S) white amorphous solid, yield: 75%, m.p: 183 – 184°C,Rf= 0.45(ethylacetate/n-hexane2:8),IR (cm−1):3265.75 (N–H), 3208.56 (O–H), 2986.45 (aliph. C-H), 1682.92 (C=O), 1574.25 (ArC=C),1488.46(C=S),1229.66(C–O), 1HNMR(
δ
ppm,400 mHz, DMSO-d6): 1.99 (s, 3H, CH3); 3.65 (s, 3H, CH3); 5.26 (s, 1H,CH); 6.62 (s,1H, ArH); 6.78 (d, 1H,ArH 3JHH = 8.00Hz);
6.81 (d, 2H,ArH 3JHH = 8.00Hz); 7.07 (t, 1H,ArH); 7.40 (d, 4H, ArH 3JHH = 8.00Hz); 9.30 (s, 1H, NH); 9.44 (s, 1H, OH), 9.54 (s 1H,NH);9.87(s,1H,NH),13CNMR(
δ
ppm, 100MHz,DMSO-d6):16.95(CH3);55.70(CH);55.70(OCH3);108.03(ArC);113.77(ArC);
114.24(ArC);115.12(ArC);117.37(ArC);121.84(ArC);130.05(ArC);
132.59 (ArC); 135.27 (ArC); 145.14 (ArC); 155.87 (ArC); 158.06 (ArC); 165.11 (C=O); 174.59 (C=S). LC-MSMS (m/z): [Peak Found (M−2): 368.1 (calculated (M−2): 368.4)] Fragment peaks: 291.9, 309.1,334.0.
Anal.Calcd.forC19H19N3O3S:C,61.77;H,5.18;N,11.37;S,8.68;
Found:C,61.89;H,5.25;N,11.49;S,8.79.
Compound–23: N-(4-methoxyphenyl)-6-methyl-4-styryl-2- thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxamide (C21H21N3O2S) yellow amorphoussolid, yield: 73%, m.p: 173 – 175°C, Rf = 0.75 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3244.30 (N–H), 3231.43
(N–H), 3067.00 (ArC–H), 3006.95 (aliph. C-H), 1681.49 (aliph.
C=C), 1622.87 (C=O), 1512.77 (ArC=C), 1438.42 (C=S), 1178.19 (C–O), 1H NMR(
δ
ppm, 400 mHz, DMSO-d6): 1.95 (s,3H,CH3);3.65 (s, 3H, OCH3); 4.15 (s, 1H, CH); 6.02 (m, 1H, CH=CH);
6.07 (m, 1H, CH=CH); 6.49 (d, 2H, ArH 3JHH = 16.00Hz); 6.69 (d, 2H, ArH 3JHH = 8.00Hz); 6.79 (s, 1H, NH); 7.19 (d, 2H, ArH 3JHH = 8.00Hz); 7.25 (t, 1H, ArH 3JHH = 4.00Hz); 7.32 (d, 2H, ArH 3JHH = 8.00Hz); 9.83 (s, 1H, NH); 9.80 (s, 1H, NH).
LC-MSMS (m/z): [Peak Found (M+2): 381.2 (calculated (M+2):
381.4)].
Anal. Calcd. for C21H21N3O2S: C, 66.47; H, 5.58; N, 11.07; S, 8.45;Found:C,66.56;H,5.72;N,11.25;S,8.58.
Compound–24: N-(4-methoxyphenyl)-6-methyl-2-thioxo- 4-(p-tolyl)-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C20H21N3O2S) white amorphous solid, yield: 95%, m.p: 188 – 190°C,Rf = 0.75(ethylacetate/n-hexane 2:8),IR (cm−1):3231.43 (N–H), 3018.39(ArC–H), 1684.35(C=O),1512.77(ArC=C), 1481.31 (C=S),1253.97 (C–O),832.17(pC–H),1HNMR(
δ
ppm,400mHz,DMSO-d6):2.01(s,3H,CH3);2.21(s,3H,CH3);3.65(s,3H,CH3);
5.31(s,1H,CH);6.77(d,2H,ArH3JHH =8.00Hz);7.10(s,4H,ArH);
7.41(d,2H,ArH3JHH=8.00Hz);9.35(s,1H,NH);9.56(s,1H,NH);
9.91 (s, 1H, NH), 13C NMR (
δ
ppm, 400 MHz, DMSO-d6): 16.98 (CH3);21.20(CH3);55.37(CH);55.67(OCH3);107.97(ArC);114.21 (ArC); 121.71 (ArC); 126.84 (ArC); 129.65 (ArC); 132.60 (ArC);135.37 (ArC); 140.69 (ArC); 155.82 (ArC); 165.08 (C=O); 174.45 (C=S), LC-MSMS (m/z): [Peak Found (M+2): 369.7 (Calculated (M+2):369.4)]Fragmentpeaks:333.2,351.3.
Anal. Calcd. for C20H21N3O2S: C, 65.37; H, 5.76; N, 11.44; S, 8.72;Found:C,65.56;H,5.89;N,11.62;S,8.88.
Compound–25: 4-(4-bromophenyl)-N-(4-methoxyphenyl)-6- methyl-2-thioxo-1, 2, 3, 4-tetrahydropyrimidine-5-carboxamide (C19H18BrN3O2S) white amorphous solid, yield: 68%, m.p: 198 – 200°C, Rf = 0.7 (ethyl acetate/n-hexane 2:8), IR (cm−1): 3381.57 (N–H), 3204.27 (N–H), 3001.10 (ArC–H), 2963.54 (aliph. C-H), 1684.35 (C=O), 1512.77 (ArC=C), 1441.28 (C=S), 1205.35 (C–O), 509.02 (C–Br), 1H NMR (
δ
ppm, 400 mHz, DMSO-d6): 2.01 (s, 3H, CH3); 3.65 (s, 3H, CH3); 5.31 (s, 1H, CH); 6.79 (d, 2H, ArH3JHH =8.00Hz);7.15(d,2H,ArH3JHH =8.00Hz);7.40 (d,2H,ArH
3JHH = 8.00Hz); 7.53 (d, 2H, ArH 3JHH = 8.00Hz); 9.42 (s, 1H, NH); 9.59 (s,1H, NH); 10.01 (s, 1H,NH), 13C NMR (
δ
ppm, 400MHz, DMSO-d6): 17.02 (CH3); 55.06 (CH); 55.68 (OCH3); 107.36 (ArC); 114.24 (ArC); 121.40 (ArC); 121.78 (ArC); 129.15 (ArC);
132.08 (ArC); 135.90 (ArC); 142.86 (ArC); 155.89 (ArC); 164.89 (C=O); 174.63 (C=S), LC-MSMS(m/z): [Peak Found (M+2): 434.6 (Calculated(M+2):434.3)]Fragmentpeaks:418.0,422.5.
Anal. Calcd. forC19H18BrN3O2S: C, 52.79; H, 4.20; N,9.72; S, 7.42;Found:C,52.93;H,4.37;N,9.89;S,7.63.
Fig. 3. Experimental Vs predicted values of training set molecules.