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I-synthon 3-(anthracen-9-yl)-2-cyanoacryloyl chloride 4 yakhiwe futhi yasetshenziswa ukuhlanganisa izinhlobo ezahlukene zamakhemikhali e-heterocyclic asebenzayo kakhulu ngokusebenzisa ukusabela kwayo nama-nucleophile ahlukahlukene e-nitrogen. Isakhiwo senhlanganisela ngayinye ye-heterocyclic eyenziwe sachazwa kahle kusetshenziswa ukuhlaziywa kwe-spectroscopic kanye ne-elemental. Amakhemikhali ayishumi kwayishumi nantathu amasha e-heterocyclic abonise ukusebenza okukhuthazayo ngokumelene namagciwane amelana nemithi eminingi (MRSA). Phakathi kwawo, amakhemikhali angu-6, 7, 10, 13b, kanye no-14 abonise umsebenzi ophezulu kakhulu wokulwa namagciwane ngezindawo zokuvimbela eziseduze no-4 cm. Kodwa-ke, izifundo zokufaka ama-molecular docking zembule ukuthi amakhemikhali ayenezinhlobo ezahlukene zokubopha ku-protein 2a ebopha i-penicillin (PBP2a), okuwumgomo oyinhloko wokumelana ne-MRSA. Amanye amakhemikhali afana no-7, 10 no-14 abonise ukuqina okuphezulu kokubopha kanye nokuqina kokuxhumana endaweni esebenzayo ye-PBP2a uma kuqhathaniswa ne-quinazolinone ligand ehlanganisiwe. Ngokuphambene nalokho, ama-compounds 6 kanye no-13b ayenamaphuzu aphansi okufaka ama-docking kodwa asabonisa umsebenzi obalulekile wokulwa namagciwane, lapho i-compound 6 inamanani aphansi kakhulu e-MIC (9.7 μg/100 μL) kanye ne-MBC (78.125 μg/100 μL). Ukuhlaziywa kwe-docking kwembule ukusebenzisana okubalulekile okuhlanganisa ukubopha kwe-hydrogen kanye ne-π-stacking, ikakhulukazi ngama-residues afana ne-Lys 273, Lys 316 kanye ne-Arg 298, ahlonzwe njengokuxhumana ne-ligand ehlanganisiwe esakhiweni sekristalu se-PBP2a. La ma-residues abalulekile emsebenzini we-enzymatic we-PBP2a. Le miphumela iphakamisa ukuthi ama-compounds ahlanganisiwe angasebenza njengemithi ethembisayo yokulwa ne-MRSA, egcizelela ukubaluleka kokuhlanganisa i-molecular docking ne-bioassays ukuhlonza abantu abafanelekayo kwezokwelapha.
Eminyakeni embalwa yokuqala yaleli khulu leminyaka, imizamo yocwaningo yayigxile kakhulu ekuthuthukiseni izinqubo ezintsha nezilula kanye nezindlela zokuhlanganiswa kwezinhlelo eziningana ezintsha ze-heterocyclic ezinomsebenzi wokulwa namagciwane kusetshenziswa izinto zokuqala ezitholakala kalula.
Izinto ze-Acrylonitrile zibhekwa njengezinto ezibalulekile zokuqala ukwenziwa kwezinhlelo eziningi eziphawulekayo ze-heterocyclic ngoba zingamakhemikhali asabela kakhulu. Ngaphezu kwalokho, izinto ezisetshenziswayo ze-2-cyanoacryloyl chloride zisetshenziswe kabanzi eminyakeni yamuva nje ekuthuthukiseni nasekuhlanganiseni imikhiqizo ebaluleke kakhulu emkhakheni wezicelo zemithi, njengezidakamizwa eziphakathi kwe-1,2,3, izandulela ze-anti-HIV, i-antiviral, i-anticancer, i-antibacterial, i-antidepressant kanye ne-antioxidant 4,5,6,7,8,9,10. Muva nje, ukusebenza kahle kwezinto eziphilayo kwe-anthracene kanye nezinto ezisetshenziswayo, okuhlanganisa ne-antibiotic yazo, i-anticancer11,12, i-antibacterial13,14,15 kanye nezakhiwo zokubulala izinambuzane16,17, kuye kwadonsela ukunaka okukhulu18,19,20,21. Izinto ezisetshenziswayo zokulwa namagciwane eziqukethe izinto ze-acrylonitrile kanye ne-anthracene ziboniswe kuZithombe 1 no-2.
Ngokusho kwe-World Health Organization (WHO) (2021), ukumelana namagciwane (i-AMR) kuyisongo somhlaba wonke empilweni nasekuthuthukisweni22,23,24,25. Iziguli azikwazi ukwelashwa, okuholela ekuhlaleni isikhathi eside esibhedlela kanye nesidingo semithi ebiza kakhulu, kanye nokwanda kokufa nokukhubazeka. Ukuntuleka kwemithi elwa namagciwane esebenzayo kuvame ukuholela ekwehlulekeni kokwelashwa kwezifo ezahlukahlukene, ikakhulukazi ngesikhathi sokwelashwa ngamakhemikhali kanye nokuhlinzwa okukhulu.
Ngokusho kombiko we-World Health Organisation ka-2024, i-Staphylococcus aureus (MRSA) ne-E. coli ezingamelana ne-methicillin zifakiwe ohlwini lwezifo ezibangelwa amagciwane ezibaluleke kakhulu. Womabili amagciwane amelana namagciwane amaningi, ngakho-ke amelela izifo okunzima ukuzelapha nokuzilawula, futhi kunesidingo esiphuthumayo sokuthuthukisa amakhemikhali amasha futhi asebenzayo okulwa namagciwane ukuze kuxazululwe le nkinga. I-Anthracene kanye nemikhiqizo yayo iyimithi yokulwa namagciwane eyaziwayo engasebenza kumagciwane amabili e-Gram-positive kanye ne-Gram-negative. Inhloso yalolu cwaningo ukukhiqiza into entsha engalwa nalezi zifo ezibangelwa amagciwane eziyingozi empilweni.
I-World Health Organization (WHO) ibika ukuthi amagciwane amaningi amagciwane amelana nama-antibiotic amaningi, okuhlanganisa ne-methicillin-resistant Staphylococcus aureus (MRSA), imbangela evamile yokutheleleka emphakathini nasezindaweni zokunakekelwa kwempilo. Iziguli ezinezifo ze-MRSA kubikwa ukuthi zinezinga lokufa eliphakeme ngo-64% kunalezo ezinezifo ezithathelwana ngemithi. Ngaphezu kwalokho, i-E. coli ibeka ingozi yomhlaba wonke ngoba umugqa wokugcina wokuzivikela ku-Enterobacteriaceae engamelana ne-carbapenem (okungukuthi, i-E. coli) yi-colistin, kodwa amagciwane angamelana ne-colistin asanda kubikwa emazweni amaningana. 22,23,24,25
Ngakho-ke, ngokusho kwe-World Health Organisation Global Action Plan on Antimicrobial Resistance26, kunesidingo esiphuthumayo sokutholakala nokuhlanganiswa kwemithi emisha yokulwa namagciwane. Amandla amakhulu e-anthracene ne-acrylonitrile njengemithi yokulwa namagciwane27, i-antifungal28, i-anticancer29 kanye ne-antioxidant30 aqokonyiswe emaphephandabeni amaningi ashicilelwe. Kulokhu, kungashiwo ukuthi lezi zinto ezitholakalayo ziyizindlela ezinhle zokusetshenziswa ngokumelene ne-Staphylococcus aureus (MRSA) engamelana ne-methicillin.
Ukubuyekezwa kwezincwadi zangaphambilini kusishukumisele ukuba sihlanganise izinto ezintsha ezitholakala kulezi zigaba. Ngakho-ke, lolu cwaningo luhlose ukuthuthukisa izinhlelo ezintsha ze-heterocyclic eziqukethe i-anthracene kanye ne-acrylonitrile, ukuhlola ukusebenza kwazo okulwa namagciwane kanye nokulwa namagciwane, kanye nokuphenya ukusebenzisana kwazo okungenzeka kokubopha ne-penicillin-binding protein 2a (PBP2a) ngokufaka ama-molecule. Ngokwakhela ezifundweni zangaphambilini, lolu cwaningo luqhubeke nokuhlanganiswa, ukuhlolwa kwezinto eziphilayo, kanye nokuhlaziywa kokubala kwezinhlelo ze-heterocyclic ukuze kutholakale ama-agent athembisayo e-antimethicillin-resistant Staphylococcus aureus (MRSA) anomsebenzi onamandla wokuvimbela i-PBP2a31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49.
Ucwaningo lwethu lwamanje lugxile ekuhlolweni kokwenziwa kanye nokulwa namagciwane kwamakhemikhali amasha e-heterocyclic aqukethe i-anthracene kanye ne-acrylonitrile. I-3-(anthracen-9-yl)-2-cyanoacryloyl chloride 4 yalungiswa futhi yasetshenziswa njengebhloko yokwakha izinhlelo ezintsha ze-heterocyclic.
Isakhiwo se-compound 4 sinqunywe kusetshenziswa idatha ye-spectral. I-spectrum ye-1H-NMR ibonise ukuba khona kwe-CH= ku-9.26 ppm, i-spectrum ye-IR ibonise ukuba khona kweqembu le-carbonyl ku-1737 cm−1 kanye neqembu le-cyano ku-2224 cm−1, kanti i-spectrum ye-13CNMR nayo iqinisekisile isakhiwo esiphakanyisiwe (bheka isigaba sokuhlola).
Ukwenziwa kwe-3-(anthracen-9-yl)-2-cyanoacryloyl chloride 4 kwenziwe nge-hydrolysis yamaqembu e-aromatic 250, 41, 42, 53 ngesisombululo se-ethanolic sodium hydroxide (10%) ukuze kunikezwe ama-acid angu-354, 45, 56, abese ephathwa nge-thionyl chloride emanzini okugeza ukuze kunikezwe i-acryloyl chloride derivative 4 enenzuzo ephezulu (88.5%), njengoba kuboniswe kuMfanekiso 3.
Ukuze kudalwe ama-compounds amasha e-heterocyclic anamandla okubulala amagciwane alindelekile, kwenziwa ukusabela kwe-acyl chloride 4 ngama-dinucleophile ahlukahlukene.
I-acid chloride 4 yaphathwa nge-hydrazine hydrate ku-0° ihora elilodwa. Ngeshwa, i-pyrazolone 5 ayitholakalanga. Lo mkhiqizo wawuyi-acrylamide derivative okwathi isakhiwo sayo saqinisekiswa idatha ye-spectral. I-spectrum yayo ye-IR ibonise ama-absorption bands e-C=O ku-1720 cm−1, C≡N ku-2228 cm−1 kanye ne-NH ku-3424 cm−1. I-spectrum ye-1H-NMR ibonise isignali ye-exchange singlet yama-olefin proton nama-NH proton ku-9.3 ppm (bheka iSigaba Sokuhlola).
Ama-moles amabili e-acid chloride 4 asabela nge-mole eyodwa ye-phenylhydrazine ukuze anikeze i-N-phenylacryloylhydrazine derivative 7 isivuno esihle (77%) (Isithombe 5). Isakhiwo se-7 siqinisekiswe yidatha ye-infrared spectroscopy, ebonise ukumuncwa kwamaqembu amabili e-C=O ku-1691 kanye no-1671 cm−1, ukumuncwa kweqembu le-CN ku-2222 cm−1 kanye nokumuncwa kweqembu le-NH ku-3245 cm−1, kanye ne-spectrum yayo ye-1H-NMR ebonise iqembu le-CH ku-9.15 kanye no-8.81 ppm kanye ne-NH proton ku-10.88 ppm (bheka isigaba sokuhlola).
Kulolu cwaningo, kuhlolwe ukusabela kwe-acyl chloride 4 ngama-1,3-dinucleophiles. Ukwelashwa kwe-acyl chloride 4 nge-2-aminopyridine ku-1,4-dioxane nge-TEA njengesisekelo ekushiseni kwegumbi kunikeze i-acrylamide derivative 8 (Isithombe 5), isakhiwo sayo esatholakala kusetshenziswa idatha ye-spectral. Ama-spectra e-IR abonise ama-absorption bands e-cyano elula ku-2222 cm−1, i-NH ku-3148 cm−1, kanye ne-carbonyl ku-1665 cm−1; Ama-spectra e-1H NMR aqinisekisile ukuba khona kwama-olefin proton ku-9.14 ppm (bheka iSigaba Sokuhlola).
I-Compound 4 isabela ne-thiourea ukuze inikeze i-pyrimidinethione 9; i-compound 4 isabela ne-thiosemicarbazide ukuze inikeze i-thiopyrazole derivative 10 (Isithombe 5). Izakhiwo zama-compound 9 no-10 ziqinisekiswe ngokuhlaziywa kwe-spectral kanye ne-elemental (bheka isigaba sokuhlola).
I-Tetrazine-3-thiol 11 yalungiswa ngokusabela kwe-compound 4 ne-thiocarbazide njenge-1,4-dinucleophile (Isithombe 5), futhi isakhiwo sayo saqinisekiswa yi-spectroscopy kanye nokuhlaziywa kwezinto eziyisisekelo. Ku-spectrum ye-infrared, isibopho se-C=N savela ku-1619 cm−1. Ngesikhathi esifanayo, i-spectrum yayo ye-1H-NMR yagcina izimpawu ze-multiplate zama-proton aromatic ku-7.78–8.66 ppm kanye nama-proton e-SH ku-3.31 ppm (bheka iSigaba Sokuhlola).
I-Acryloyl chloride 4 iphendula ne-1,2-diaminobenzene, i-2-aminothiophenol, i-anthranilic acid, i-1,2-diaminoethane, kanye ne-ethanolamine njenge-1,4-dinucleophiles ukuze kwakhiwe izinhlelo ezintsha ze-heterocyclic (13–16).
Izakhiwo zala ma-compound asanda kuhlanganiswa zaqinisekiswa ngokuhlaziywa kwe-spectral kanye ne-elemental (bheka isigaba sokuhlola). I-2-Hydroxyphenylacrylamide derivative 17 yatholakala ngokusabela nge-2-aminophenol njenge-dinucleophile (Isithombe 6), futhi isakhiwo sayo saqinisekiswa ngokuhlaziywa kwe-spectral kanye ne-elemental. I-infrared spectrum ye-compound 17 ibonise ukuthi izimpawu ze-C=O kanye ne-C≡N zavela ku-1681 kanye no-2226 cm−1, ngokulandelana. Phakathi naleso sikhathi, i-spectrum yayo ye-1H-NMR igcine isignali ye-singlet ye-olefin proton ku-9.19 ppm, kanti i-OH proton yavela ku-9.82 ppm (bheka isigaba sokuhlola).
Ukusabela kwe-acid chloride 4 ne-nucleophile eyodwa (isb., i-ethylamine, i-4-toluidine, kanye ne-4-methoxyaniline) ku-dioxane njenge-solvent kanye ne-TEA njenge-catalyst ekushiseni kwegumbi kunikeze ama-acrylamide derivatives aluhlaza okwesibhakabhaka angu-18, 19a, kanye no-19b. Idatha ye-elemental kanye ne-spectral yama-compounds angu-18, 19a, kanye no-19b iqinisekisile izakhiwo zalezi zi-derivatives (bheka iSigaba Sokuhlola) (Isithombe 7).
Ngemva kokuhlola umsebenzi wokulwa namagciwane wamakhemikhali ahlukahlukene okwenziwa, kwatholakala imiphumela ehlukene njengoba kuboniswe kuThebula 1 kanye noMfanekiso 8 (bheka ifayela lesithombe). Wonke amakhemikhali ahlolwe abonise amazinga ahlukene okuvinjelwa ngokumelene nebhaktheriya eliyi-Gram-positive MRSA, kuyilapho i-bacterium engeyi-Gram-negative Escherichia coli ibonise ukumelana okuphelele nawo wonke amakhemikhali. Amakhemikhali ahlolwe angahlukaniswa ngezigaba ezintathu ngokusekelwe kububanzi bendawo yokuvinjelwa ngokumelene ne-MRSA. Isigaba sokuqala sasisebenza kakhulu futhi sasinezakhi ezinhlanu (6, 7, 10, 13b kanye no-14). Ububanzi bendawo yokuvinjelwa yala makhemikhali babuseduze no-4 cm; amakhemikhali asebenza kakhulu kulesi sigaba kwakuyizakhi 6 kanye no-13b. Isigaba sesibili sasisebenza ngokulinganisela futhi sasinezakhi ezinhlanu (11, 13a, 15, 18 kanye no-19a). Indawo yokuvinjelwa yala makhemikhali yayisukela ku-3.3 kuya ku-3.65 cm, kanti i-compound 11 ibonisa indawo enkulu yokuvinjelwa engu-3.65 ± 0.1 cm. Ngakolunye uhlangothi, iqembu lokugcina laliqukethe ama-compound amathathu (8, 17 kanye no-19b) anomsebenzi ophansi kakhulu wokulwa namagciwane (ngaphansi kuka-3 cm). Isibalo 9 sibonisa ukusatshalaliswa kwezindawo ezahlukene zokuvinjelwa.
Uphenyo olwengeziwe lomsebenzi wokulwa namagciwane wamakhemikhali avivinyiwe luhilele ukunqunywa kwe-MIC kanye ne-MBC yenhlanganisela ngayinye. Imiphumela yahluka kancane (njengoba kuboniswe kuThebula 2, 3 kanye noMfanekiso 10 (bheka ifayela lesithombe)), lapho ama-compound 7, 11, 13a kanye no-15 kubonakala sengathi ahlelwa kabusha njengama-compound amahle kakhulu. Ayenamanani aphansi kakhulu e-MIC kanye ne-MBC (39.06 μg/100 μL). Nakuba ama-compound 7 kanye no-8 ayenamanani aphansi e-MIC (9.7 μg/100 μL), amanani awo e-MBC ayephezulu (78.125 μg/100 μL). Ngakho-ke, ayebhekwa njengobuthakathaka kunamakhemikhali okukhulunywe ngawo ngaphambili. Kodwa-ke, la ma-compound ayisithupha ayesebenza kahle kakhulu kulawo avivinyiwe, njengoba amanani awo e-MBC ayengaphansi kuka-100 μg/100 μL.
Ama-Compound (10, 14, 18 kanye no-19b) ayengasebenzi kahle uma kuqhathaniswa namanye ama-compound avivinyiwe njengoba amanani awo e-MBC ayesukela ku-156 kuya ku-312 μg/100 μL. Ngakolunye uhlangothi, ama-compound (8, 17 kanye no-19a) ayengathembisi kangako njengoba ayenamanani aphezulu kakhulu e-MBC (625, 625 kanye no-1250 μg/100 μL, ngokulandelana).
Okokugcina, ngokwamazinga okubekezelelana aboniswe kuThebula 3, ama-compound avivinyiwe angahlukaniswa ngezigaba ezimbili ngokusekelwe endleleni yawo yokusebenza: ama-compounds anomphumela wokubulala amagciwane (7, 8, 10, 11, 13a, 15, 18, 19b) kanye nama-compounds anomphumela wokulwa namagciwane (6, 13b, 14, 17, 19a). Phakathi kwawo, ama-compounds 7, 11, 13a kanye no-15 ayathandwa, abonisa umsebenzi wokubulala ngokuhlushwa okuphansi kakhulu (39.06 μg/100 μL).
Amakhemikhali ayishumi kwayishumi nantathu ahlolwe abonise ukuthi angakwazi ukumelana ne-methicillin-resistant antibiotic Staphylococcus aureus (MRSA) engamelani namagciwane. Ngakho-ke, ukuhlolwa okwengeziwe ngamagciwane amelana namagciwane amaningi (ikakhulukazi ama-isolates endawo ahlanganisa amagciwane e-Gram-positive kanye ne-Gram-negative) kanye nemvubelo ye-pathogenic kuyanconywa, kanye nokuhlolwa kwe-cytotoxic kwenhlanganisela ngayinye ukuhlola ukuphepha kwayo.
Kwenziwe izifundo zokufaka ama-molecule ukuze kuhlolwe amandla amakhemikhali ahlanganisiwe njengezithiyo zeprotheyini ebopha i-penicillin 2a (PBP2a) ku-Staphylococcus aureus (MRSA) engamelana ne-methicillin. I-PBP2a iyi-enzyme eyinhloko ehilelekile ekuhlanganisweni kodonga lweseli lamagciwane, futhi ukuvinjelwa kwale enzyme kuphazamisa ukwakheka kodonga lweseli, ekugcineni okuholela ekuqhekekeni kwamagciwane kanye nokufa kweseli1. Imiphumela yokubeka ama-docking ibhalwe kuThebula 4 futhi ichazwe ngokuningiliziwe kufayela ledatha elingeziwe, futhi imiphumela ikhombisa ukuthi amakhemikhali amaningana abonise ukuqina kokubopha okuqinile kwe-PBP2a, ikakhulukazi izinsalela zesayithi ezisebenzayo ezibalulekile njenge-Lys 273, Lys 316, kanye ne-Arg 298. Ukusebenzisana, okuhlanganisa ukubopha kwe-hydrogen kanye ne-π-stacking, kwakufana kakhulu nokwe-co-crystallized quinazolinone ligand (CCL), okubonisa amandla ala makhemikhali njengezithiyo ezinamandla.
Idatha ye-molecular docking, kanye nezinye izilinganiso zokubala, iphakamise ngokuqinile ukuthi ukuvinjelwa kwe-PBP2a kwakuyiyona ndlela eyinhloko ebangela umsebenzi we-antibacterial obonwe walawa ma-compound. Amanani e-docking kanye namanani e-root mean square deviation (RMSD) ​​aveze ngokwengeziwe i-binding affinity kanye nokuzinza, okusekela lo mbono. Njengoba kuboniswe kuThebula 4, ngenkathi ama-compound amaningana ebonise i-binding affinity enhle, amanye ama-compound (isb., 7, 9, 10, kanye no-14) ayenamaphuzu aphezulu e-docking kune-ligand ehlanganisiwe, okubonisa ukuthi angaba nokusebenzisana okuqinile nama-residues asebenzayo e-PBP2a. Kodwa-ke, ama-compound asebenzayo kakhulu i-6 kanye ne-13b abonise amaphuzu aphansi kancane e-docking (-5.98 kanye ne--5.63, ngokulandelana) uma kuqhathaniswa namanye ama-ligand. Lokhu kusikisela ukuthi yize amaphuzu e-docking angasetshenziswa ukubikezela i-binding affinity, ezinye izici (isb., ukuzinza kwe-ligand kanye nokusebenzisana kwama-molecule endaweni yezinto eziphilayo) nazo zidlala indima ebalulekile ekunqumeni umsebenzi we-antibacterial. Okuphawulekayo ukuthi amanani e-RMSD azo zonke izinhlanganisela ezenziwe zazingaphansi kuka-2 Å, okuqinisekisa ukuthi ukuma kwazo kokumisa kuhambisana nesakhiwo nokwakheka kokubopha kwe-ligand ehlanganisiwe, okusekela ngokwengeziwe amandla azo njengezithibi ezinamandla ze-PBP2a.
Nakuba amaphuzu okufaka ama-docking kanye namanani e-RMS anikeza izibikezelo ezibalulekile, ukuhlangana phakathi kwale miphumela yokufaka ama-docking kanye nomsebenzi wokulwa namagciwane akucaci ngaso sonke isikhathi ekuqaleni. Nakuba ukuvinjelwa kwe-PBP2a kusekelwa kakhulu njengento ebalulekile ethonya umsebenzi wokulwa namagciwane, umehluko oningana uphakamisa ukuthi ezinye izakhiwo zezinto eziphilayo nazo zidlala indima ebalulekile. Ama-Compounds 6 kanye no-13b abonise umsebenzi wokulwa namagciwane ophezulu kakhulu, kokubili ububanzi bendawo yokuvinjelwa obungu-4 cm kanye namanani aphansi kakhulu e-MIC (9.7 μg/100 μL) kanye ne-MBC (78.125 μg/100 μL), naphezu kwamaphuzu awo aphansi okufaka ama-docking uma kuqhathaniswa nama-compounds 7, 9, 10 kanye no-14. Lokhu kusikisela ukuthi nakuba ukuvinjelwa kwe-PBP2a kunegalelo emsebenzini wokulwa namagciwane, izici ezifana nokuncibilika, ukutholakala kwezinto eziphilayo kanye nokuguquguquka kokuxhumana endaweni yamagciwane nakho kuthinta umsebenzi wonke. Isibalo 11 sibonisa izimo zazo zokufaka ama-docking, okubonisa ukuthi womabili ama-compound, ngisho namaphuzu okubopha aphansi, asakwazi ukusebenzisana nezinsalela ezibalulekile ze-PBP2a, okungenzeka kuqinise inkimbinkimbi yokuvinjelwa. Lokhu kugqamisa ukuthi nakuba ukugoqwa kwama-molecule kunikeza ukuqonda okubalulekile ekuvinjelweni kwe-PBP2a, ezinye izici zebhayoloji kumele zicatshangelwe ukuze kuqondwe ngokugcwele imiphumela yangempela yalezi zinhlanganisela yokulwa namagciwane.
Kusetshenziswa isakhiwo sekristalu se-PBP2a (PDB ID: 4CJN), kwakhiwa amamephu okusebenzisana kwe-2D kanye ne-3D amakhemikhali asebenza kakhulu i-6 kanye ne-13b afakwe iphrotheni ebopha i-penicillin i-2a (PBP2a) ye-Staphylococcus aureus engamelana ne-methicillin (MRSA). Lawa mamephu aqhathanisa amaphethini okusebenzisana kwalawa makhemikhali ne-quinazolinone ligand (CCL) efakwe kabusha, eqokomisa ukusebenzisana okubalulekile njengokubopha i-hydrogen, i-π-stacking, kanye nokusebenzisana kwe-ionic.
Kubonwe iphethini efanayo ye-compound 7, ebonise isilinganiso esiphezulu sokudokha (-6.32) kanye nobubanzi obufanayo be-inhibition zone (3.9 cm) ne-compound 10. Kodwa-ke, i-MIC yayo (39.08 μg/100 μL) kanye ne-MBC (39.06 μg/100 μL) yayiphakeme kakhulu, okubonisa ukuthi idinga amazinga aphezulu ukuze ibonise umphumela wokulwa namagciwane. Lokhu kusikisela ukuthi yize i-compound 7 ibonise ukuqina okuqinile kokubopha ezifundweni zokudokha, izici ezifana nokutholakala kwe-bioavailability, ukuthathwa kwamaseli, noma ezinye izakhiwo ze-physicochemical zinganciphisa ukusebenza kwayo kwezinto eziphilayo. Nakuba i-compound 7 ibonise izakhiwo zokubulala amagciwane, yayingasebenzi kahle ekuvimbeleni ukukhula kwamagciwane uma kuqhathaniswa nama-compound 6 kanye no-13b.
I-Compound 10 ibonise umehluko omkhulu kakhulu ngesilinganiso esiphezulu kakhulu sokumisa (-6.40), okubonisa ukubopha okuqinile ku-PBP2a. Kodwa-ke, indawo yayo yobubanzi bokuvimbela (3.9 cm) yayifana ne-compound 7, kanti i-MBC yayo (312 μg/100 μL) yayiphakeme kakhulu kune-compound 6, 7, kanye ne-13b, okubonisa umsebenzi obuthakathaka wokubulala amagciwane. Lokhu kusikisela ukuthi naphezu kwezibikezelo ezinhle zokumisa, i-compound 10 yayingasebenzi kahle ekubulaleni i-MRSA ngenxa yezinye izici ezivimbelayo njengokuncibilika, ukuzinza, noma ukungena kahle kwe-membrane yebhaktheriya. Le miphumela isekela ukuqonda ukuthi ngenkathi ukuvinjelwa kwe-PBP2a kudlala indima ebalulekile emsebenzini wokulwa namagciwane, akuchazi ngokugcwele umehluko womsebenzi webhayoloji obonwe phakathi kwamakhemikhali avivinyiwe. Lo mehluko usikisela ukuthi kudingeka ukuhlaziywa okwengeziwe kokuhlola kanye nokuhlolwa okujulile kwebhayoloji ukuze kucaciswe ngokugcwele izindlela zokulwa namagciwane ezihilelekile.
Ukufakwa kwama-molecule kuphumela kuThebula 4 kanye neFayili Yedatha Engeziwe kuqokomisa ubudlelwano obuyinkimbinkimbi phakathi kwamaphuzu okufakwa kwama-docking kanye nomsebenzi wokulwa namagciwane. Nakuba ama-compounds 6 kanye no-13b enezibalo eziphansi zokufakwa kwama-docking kune-compounds 7, 9, 10, kanye no-14, abonisa umsebenzi ophezulu kakhulu wokulwa namagciwane. Amamephu awo okusebenzisana (aboniswe kuMfanekiso 11) abonisa ukuthi naphezu kwamaphuzu awo aphansi okubopha, asakha izibopho ze-hydrogen ezibalulekile kanye nokusebenzisana kwe-π-stacking nezinsalela ezibalulekile ze-PBP2a ezingazinzisa i-enzyme-inhibitor complex ngendlela ezuzisayo ngokwebhayoloji. Naphezu kwamaphuzu aphansi okufakwa kwama-docking angu-6 no-13b, umsebenzi wawo othuthukisiwe wokulwa namagciwane usikisela ukuthi ezinye izakhiwo ezifana nokuncibilika, ukuzinza, kanye nokumuncwa kwamaseli kufanele kucatshangelwe kanye nedatha yokufakwa kwama-docking lapho kuhlolwa amandla okuvimbela. Lokhu kugqamisa ukubaluleka kokuhlanganisa izifundo zokufakwa kwama-docking nokuhlaziywa kokulwa namagciwane okuhlola ukuze kuhlolwe ngokunembile amandla okwelapha ama-compounds amasha.
Le miphumela igcizelela ukuthi nakuba ukugoqwa kwama-molecule kuyithuluzi elinamandla lokubikezela ukuhlangana kokubopha kanye nokuhlonza izindlela ezingaba khona zokuvimbela, akufanele kuthenjwe kuphela ukunquma ukusebenza kahle kwamagciwane. Idatha yama-molecule isikisela ukuthi ukuvimbela kwe-PBP2a kuyisici esiyinhloko esithonya umsebenzi wamagciwane, kodwa izinguquko emsebenzini wezinto eziphilayo zisikisela ukuthi ezinye izakhiwo ze-physicochemical kanye ne-pharmacokinetic kumele zithuthukiswe ukuze kuthuthukiswe ukusebenza kahle kokwelapha. Izifundo zesikhathi esizayo kufanele zigxile ekwenzeni ngcono isakhiwo samakhemikhali samakhemikhali 7 no-10 ukuze kuthuthukiswe ukutholakala kwezinto eziphilayo kanye nokuthathwa kwamaseli, kuqinisekiswe ukuthi ukusebenzisana okunamandla kokugoqwa kuhunyushwa kube umsebenzi wangempela wamagciwane. Izifundo ezengeziwe, kufaka phakathi ukuhlolwa okwengeziwe kwe-bioassays kanye nokuhlaziywa kobudlelwano besakhiwo-umsebenzi (SAR), kuzobaluleka kakhulu ekuqondeni kwethu ukuthi la makhemikhali asebenza kanjani njengezithibi ze-PBP2a kanye nokuthuthukisa ama-antimicrobial agents asebenza kahle kakhulu.
Ama-compound akhiwe kusuka ku-3-(anthracen-9-yl)-2-cyanoacryloyl chloride 4 abonise amazinga ahlukahlukene omsebenzi wokulwa namagciwane, kanti ama-compound amaningana abonisa ukuvinjelwa okuphawulekayo kwe-Staphylococcus aureus (MRSA) engamelana ne-methicillin. Ukuhlaziywa kobudlelwano bomsebenzi nesakhiwo (SAR) kwembule izici ezibalulekile zesakhiwo ezisekela ukusebenza kahle kwala ma-compound okulwa namagciwane.
Ukuba khona kwamaqembu e-acrylonitrile kanye ne-anthracene kubonakale kubalulekile ekuthuthukiseni umsebenzi wokulwa namagciwane. Iqembu le-nitrile elisabela kakhulu ku-acrylonitrile liyadingeka ukuze kube lula ukusebenzisana namaprotheni ebhaktheriya, ngaleyo ndlela lifaka isandla ezicini zokulwa namagciwane zekhompiyutha. Amakhompiyutha aqukethe i-acrylonitrile kanye ne-anthracene abonisa njalo imiphumela enamandla yokulwa namagciwane. Iphunga elimnandi leqembu le-anthracene laqhubeka nokuzinzisa la makhompiyutha, okungenzeka athuthukise umsebenzi wawo webhayoloji.
Ukwethulwa kwezindandatho ze-heterocyclic kuthuthukise kakhulu ukusebenza kahle kwe-antibacterial kwezinhlobo eziningana ze-derivatives. Ikakhulukazi, i-benzothiazole derivative 13b kanye ne-acrylhydrazide derivative 6 kubonise umsebenzi ophezulu kakhulu we-antibacterial nge-inhibition zone engaba ngu-4 cm. Lezi zinhlobo ze-heterocyclic derivatives zibonise imiphumela ebaluleke kakhulu yebhayoloji, okubonisa ukuthi isakhiwo se-heterocyclic sidlala indima ebalulekile emiphumeleni ye-antibacterial. Ngokufanayo, i-pyrimidinethione ku-compound 9, i-thiopyrazole ku-compound 10, kanye ne-tetrazine ring ku-compound 11 kunegalelo ezimpahleni ze-antibacterial zalezi zinhlanganisela, okugcizelela kakhulu ukubaluleka kokuguqulwa kwe-heterocyclic.
Phakathi kwamakhemikhali akhiwe, u-6 no-13b bavelele ngemisebenzi yabo emihle kakhulu yokulwa namagciwane. I-minimum inhibitory concentration (MIC) ye-compound 6 yayingu-9.7 μg/100 μL, kanti i-minimum inhibitory concentration (MBC) yayingu-78.125 μg/100 μL, okugqamisa ikhono layo elihle kakhulu lokususa i-methicillin-resistant Staphylococcus aureus (MRSA). Ngokufanayo, i-compound 13b yayinendawo yokuvimbela engu-4 cm kanye namanani aphansi e-MIC kanye ne-MBC, okuqinisekisa umsebenzi wayo onamandla wokulwa namagciwane. Le miphumela igqamisa izindima ezibalulekile zamaqembu asebenzayo e-acrylohydrazide kanye ne-benzothiazole ekunqumeni ukusebenza kahle kwalawa makhemikhali.
Ngokuphambene nalokho, ama-compounds 7, 10, kanye no-14 abonise umsebenzi ophakathi wokulwa namagciwane ngezindawo zokuvimbela ezisukela ku-3.65 kuya ku-3.9 cm. Lawa ma-compounds ayedinga amazinga aphezulu ukuze abulale ngokuphelele ama-bacteria, njengoba kuboniswa amanani awo aphezulu e-MIC kanye ne-MBC. Nakuba la ma-compounds ayengasebenzi kangako kunama-compounds 6 kanye no-13b, asabonisa amandla amakhulu okulwa namagciwane, okuphakamisa ukuthi ukufakwa kwezingxenye ze-acrylonitrile kanye ne-anthracene eringini ye-heterocyclic kunegalelo emphumeleni wazo wokulwa namagciwane.
Ama-compound anezindlela ezahlukene zokusebenza, amanye abonisa izakhiwo zokubulala amagciwane kanti amanye abonisa imiphumela ye-bacteriostatic. Ama-compound 7, 11, 13a, kanye no-15 abulala amagciwane futhi adinga amazinga aphansi ukuze abulale amagciwane ngokuphelele. Ngokuphambene nalokho, ama-compound 6, 13b, kanye no-14 abulala amagciwane futhi angavimbela ukukhula kwamagciwane ngamanani aphansi, kodwa adinga amazinga aphezulu ukuze abulale amagciwane ngokuphelele.
Sekukonke, ukuhlaziywa kobudlelwano besakhiwo nomsebenzi kugqamisa ukubaluleka kokwethula ama-acrylonitrile kanye nama-anthracene moieties kanye nezakhiwo ze-heterocyclic ukuze kufezwe umsebenzi obalulekile wokulwa namagciwane. Le miphumela iphakamisa ukuthi ukwenza ngcono lezi zingxenye zesakhiwo kanye nokuhlola izinguquko ezengeziwe zokuthuthukisa ukuncibilika kanye nokuvuleka kwe-membrane kungaholela ekuthuthukisweni kwemithi yokulwa ne-MRSA esebenza kahle kakhulu.
Zonke izinto ezisetshenziswayo kanye nezinyibilikisi zahlanzwa futhi zomiswa kusetshenziswa izinqubo ezijwayelekile (i-El Gomhouria, eGibhithe). Amaphuzu okuncibilika ahlolwa kusetshenziswa idivayisi ye-elekthronikhi ye-GallenKamp futhi abikwa ngaphandle kokulungiswa. Ama-spectra e-infrared (IR) (cm⁻1) aqoshwa eMnyangweni Wekhemistri, e-Faculty of Science, e-Ain Shams University kusetshenziswa ama-pellet e-potassium bromide (KBr) ku-Thermo Electron Nicolet iS10 FTIR spectrometer (Thermo Fisher Scientific, Waltham, MA, USA).
Ama-spectra e-1H NMR atholakale ku-300 MHz kusetshenziswa i-GEMINI NMR spectrometer (GEMINI Manufacturing & Engineering, Anaheim, CA, USA) kanye ne-BRUKER 300 MHz NMR spectrometer (BRUKER Manufacturing & Engineering, Inc.). I-Tetramethylsilane (TMS) yasetshenziswa njengendinganiso yangaphakathi ene-deuterated dimethyl sulfoxide (DMSO-d₆). Izilinganiso ze-NMR zenziwe e-Faculty of Science, eCairo University, eGiza, eGibhithe. Ukuhlaziywa kwe-Elemental (CHN) kwenziwa kusetshenziswa i-Perkin-Elmer 2400 Elemental Analyzer futhi imiphumela etholakele ivumelana kahle namanani abaliwe.
Ingxube ye-asidi 3 (5 mmol) kanye ne-thionyl chloride (5 ml) yashiswa ebhavini lamanzi ku-65 °C amahora ama-4. I-thionyl chloride eyengeziwe yasuswa ngokucwiliswa ngaphansi kwengcindezi encishisiwe. Okuqinile okubomvu okwavela kwaqoqwa futhi kwasetshenziswa ngaphandle kokuhlanzwa okwengeziwe. Iphuzu lokuncibilika: 200-202 °C, isivuno: 88.5%. IR (KBr, ν, cm−1): 2224 (C≡N), 1737 (C=O). 1H-NMR (400 MHz, DMSO-d6) δ (ppm): 9.26 (s, 1H, CH=), 7.27-8.57 (m, 9H, heteroaromatization). 13C NMR (75 MHz, DMSO-d6) δ (ppm): 115.11 (C≡N), 124.82–130.53 (CH anthracene), 155.34, 114.93 (CH=C–C=O), 162.22 (C=O); HRMS (ESI) m/z [M + H]+: 291.73111. Umhlaziyi. Kubalwe i-C18H10ClNO (291.73): C, 74.11; H, 3.46; N, 4.80. Kutholakale: C, 74.41; H, 3.34; N, 4.66%.
Ku-0°C, ama-4 (2 mmol, 0.7 g) ancibilikiswa ku-anhydrous dioxane (20 ml) kwathi i-hydrazine hydrate (2 mmol, 0.16 ml, 80%) yanezelwa ngokuwa phansi yavuselelwa ihora eli-1. I-solid evuvukele yaqoqwa ngokuhluzwa futhi yaphinde yakhiqizwa kusuka ku-ethanol ukuze kunikezwe i-compound 6.
Amakristalu aluhlaza, iphuzu lokuncibilika 190-192℃, isivuno esingu-69.36%; IR (KBr) ν=3424 (NH), 2228 (C≡N), 1720 (C=O), 1621 (C=N) cm−1. 1H-NMR (400 MHz, DMSO-d6) δ (ppm): 9.3 (br s, H, NH, engashintshaniswa), 7.69-8.51 (m, 18H, heteroaromatic), 9.16 (s, 1H, CH=), 8.54 (s, 1H, CH=); Inani elibaliwe le-C33H21N3O (475.53): C, 83.35; H, 4.45; N, 8.84. Kutholwe: C, 84.01; H, 4.38; N, 8.05%.
Ncibilikisa u-4 (2 mmol, 0.7 g) ku-20 ml yesisombululo se-anhydrous dioxane (equkethe amaconsi ambalwa e-triethylamine), engeza i-phenylhydrazine/2-aminopyridine (2 mmol) bese uvuselela ekamelweni lokushisa ihora eli-1 neli-2 ngokulandelana. Thela ingxube yokusabela eqhweni noma emanzini bese ufaka i-acid nge-hydrochloric acid encibilikisiwe. Hlunga okuqinile okuhlukanisiwe bese uphinda ufaka i-ethanol ukuze uthole u-7 bese uphinda ufaka i-benzene ukuze uthole u-8.
Amakristalu aluhlaza, iphuzu lokuncibilika 160-162℃, akhiqiza 77%; IR (KBr, ν, cm−1): 3245 (NH), 2222 (C≡N), 1691 (C=O), 1671 (C=O) cm−1. 1H-NMR (400 MHz, DMSO-d6): δ (ppm): 10.88 (s, 1H, NH, engashintshaniswa), 9.15 (s, 1H, CH=), 8.81 (s, 1H, CH=), 6.78-8.58 (m, 23H, heteroaromatic); Inani elibaliwe le-C42H26N4O2 (618.68): C, 81.54; H, 4.24; N, 9.06. Kutholwe: C, 81.96; H, 3.91; N, 8.91%.
I-4 (2 mmol, 0.7 g) yancibilikiswa ku-20 ml yesisombululo se-anhydrous dioxane (equkethe amaconsi ambalwa e-triethylamine), kwanezelwa i-2-aminopyridine (2 mmol, 0.25 g) futhi ingxube yavuselelwa ekushiseni kwegumbi amahora ama-2. Ingxube yokusabela yathelwa emanzini eqhwa futhi yafakwa i-acid nge-hydrochloric acid encibilikisiwe. I-precipitate eyakhiwe yahlungwa futhi yaphinde yakhiqizwa kusuka ku-benzene, yanikeza amakristalu aluhlaza angu-8 anephuzu lokuncibilika elingu-146-148 °C kanye nomkhiqizo ongu-82.5%; i-infrared spectrum (KBr) ν: 3148 (NH), 2222 (C≡N), 1665 (C=O) cm−1. 1H NMR (400 MHz, DMSO-d6): δ (ppm): 8.78 (s, H, NH, engashintshaniswa), 9.14 (s, 1H, CH=), 7.36-8.55 (m, 13H, heteroaromatization); Kubalwe i-C23H15N3O (348.38): C, 79.07; H, 4.33; N, 12.03. Kutholakale: C, 78.93; H, 3.97; N, 12.36%.
I-Compound 4 (2 mmol, 0.7 g) yancibilikiswa ku-20 ml ye-dioxane eyomile (equkethe amaconsi ambalwa e-triethylamine kanye no-2 mmol we-thiourea/semicarbazide) futhi yashiswa ngaphansi kwe-reflux amahora ama-2. I-solvent yashiswa ku-vacuo. I-residue yaphinde yakhiqizwa kusuka ku-dioxane ukuze inikeze ingxube.