SAMOORGANIZACIJA PAKOVANJA DIPOL-JON PIRIDONA PREKO MOLEKULA VODE

Abstract

Pažnja farmaceutske industrije u velikoj meri usmerena je na razumevanje sposobnosti molekula vode da se inkorporiraju u kristalno pakovanje organskih molekula uspostavljanjem različitih nekovalentnih intermolekulskih interakcija [1]. 2-Piridon je gradivna jedinica mnogih supstanci koje poseduju antibakterijsku, antifungalnu, antiinflamatornu, antiviralnu i antikancerogenu aktivnost [2]. U ovom radu, dva piridona, koja sadrže metil supstituisano piridinsko jezgro u položajima 2,4 (2) i 3,5 (3) i jedan piridon sa nesupstituisanim (1) piridinskim jezgrom (slika), sintetisani su GuarešiTorpeovom reakcijom kondenzacije. Jedinjenja su okarakterisana rendgenskom strukturnom analizom kao i određivanjem tačke topljenja, UV-Vis, FT-IR, 1H i 13C NMR spektroskopijom. Asimetrične jedinice jedinjenja 1·2H2O i 3·2H2O sastoje se od jednog molekula piridona i dva molekula vode, dok se u asimetričnoj jedinici jedinjenja 2·4H2O nalaze četiri molekula vode. Inverzno orijentisani molekuli uspostavljaju N– H···O vodonične veze i na taj način obrazuju (8) sintone. Tipovi vodenih kanala u supramolekulskoj arhitekturi zavise od prirode interakcija između dipol-jona. Dipol-dipol interakcije, jake i slabe vodonične veze, π···π i C–H···π interakcije, određuju pakovanje ovih molekula, pri čemu molekuli vode imaju značajnu ulogu. Kristalografski podaci: 1·2H2O: C11H14N2O4, Mr = 238,24, trikliničan sistem, prostorna grupa P , a = 7,2258(14), b = 8,0470(16), c = 11,287(2) Å, α = 70,71(3), β = 74,88(3), γ = 79,85(3)°, V = 595,1(2) Å3 , R1 = 0,0492; 2·4H2O: C13H22N2O6, Mr = 302,32, trikliničan sistem, prostorna grupa P , a = 7,4411(15), b = 10,581(2), c = 11,235(2) Å, α = 108,96(3), β = 96,14(3), γ = 107,41(3)°, V = 777,6(3) Å3 , R1 = 0,0443; 3·2H2O: C13H18N2O4, Mr = 266,29, trikliničan sistem, prostorna grupa P , a = 7,5951(8), b = 9,0353(8), c = 11,5716(10) Å, α = 82,878(7), β = 72,010(8), γ = 71,919(9)°, V = 717,62(13) Å3 , R1 = 0,0522.

The attention of pharmaceutical industry is set on understanding the ability of water molecules to accompany organic crystals through interplay of various non-covalent intermolecular interactions [1]. 2-Pyridone is found as a structural unit in many compounds with antibacterial, antifungal, anti-inflammatory, antiviral or anticancer activity [2]. In this paper, two pyridone derivatives bearing methyl substituents in the pyridine unit in positions 2,4 (2) and 3,5 (3) were synthesized via the Guareschi-Thorpe condensation as well as one pyridone without substituents (1) in the pyridine scaffold (Figure). These compounds were characterized by single-crystal X-ray analysis as well as determination of the melting points, UV-Vis, FTIR, 1H and 13C NMR spectroscopy. The asymmetric units of compounds 1·2H2O and 3·2H2O are comprised of one pyridone molecule and two water molecules, whereas the asymmetric unit of compound 2·4H2O incorporates four water molecules. Pairs of N–H···O hydrogen bonds connect inversion related molecules into the (8) synthons in the supramolecular architectures. The type of water channel depends on the nature of interactions established between zwitterions. Molecular packing is governed by dipole-dipole interactions, strong and weak hydrogen bonds, π–π and C–H···π interactions, wherein water molecules play a significant role. Crystal data: 1·2H2O: C11H14N2O4, Mr = 238.24, triclinic, space group P , a = 7.2258(14), b = 8.0470(16), c = 11.287(2) Å, α = 70.71(3), β = 74.88(3), γ = 79.85(3)°, V = 595.1(2) Å3 , R1 = 0.0492; 2·4H2O: C13H22N2O6, Mr = 302.32, triclinic, space group P , a = 7.4411(15), b = 10.581(2), c = 11.235(2) Å, α = 108.96(3), β = 96.14(3), γ = 107.41(3)°, V = 777.6(3) Å3 , R1 = 0.0443; 3·2H2O: C13H18N2O4, Mr = 266.29, triclinic, space group P , a = 7.5951(8), b = 9.0353(8), c = 11.5716(10) Å, α = 82.878(7), β = 72.010(8), γ = 71.919(9)°, V = 717.62(13) Å3 , R1 = 0.0522.