Elisei Cosovan, Victor Cosovan, Daniel A. Osborne, David H. Magers, Edward J. Valente
{"title":"7-Dimethylamino-4-Hydroxycoumarin and Derivatives: Enhanced β-Chain Hydrogen-Bonding","authors":"Elisei Cosovan, Victor Cosovan, Daniel A. Osborne, David H. Magers, Edward J. Valente","doi":"10.1007/s10870-024-01020-7","DOIUrl":"10.1007/s10870-024-01020-7","url":null,"abstract":"<div><p>\u0000 The crystal and molecular structure of 7-dimethylamino-4-hydroxycoumarin as its hydrate (<b>1</b>, C<sub>11</sub>H<sub>11</sub>NO<sub>3</sub> • H<sub>2</sub>O) has been determined. Crystals are monoclinic, space group <i>P</i>2(1)/<i>n</i> with <i>a</i> = 7.1435(4) Å, <i>b</i> = 20.1763(6) Å, <i>c</i> = 7.8590(3) Å, <i>β</i> = 110.018(5)<sup>o</sup> and V = 1064.28(8)Å<sup>3</sup> for 4 formula units per cell. Both coumarin enol ester hydroxy and carboxy groups engage in hydrogen-bonding with the water of crystallization. Several 3-substituted derivatives were prepared from this material including 7-dimethylamino-3-benzyl-4-hydroxycoumarin (<b>2</b>) and 7-dimethylaminowarfarin (<b>4</b>). Compound <b>2</b> (C<sub>18</sub>H<sub>16</sub>NO<sub>3</sub>) crystallizes in the triclinic system, space group <i>P</i>-1, with <i>a</i> = 7.0180(7) Å, <i>b</i> = 7.8143(7) Å, <i>c</i> = 14.3158(10) Å, <i>α</i> = 90.586(6)<sup>o</sup>, <i>β</i> = 94.738(5)<sup>o</sup>, <i>γ</i> = 104.639(7)<sup>o</sup>, and V = 756.57(9) Å<sup>3</sup> for 2 molecules in the cell. For compound <b>2</b>, the crystal structure shows infinite hydrogen-bonded translational β-chains linking well aligned hydroxy and ester carboxy groups with a repeat distance of 7.018 Å. The dipolar nature of the substituted 4-hydroxycoumarin strengthens the β-chains compared to unsubstituted systems in which the repeat is longer and weaker at 7.17 Å. Computations (DFT) support the bond length changes due to a dipolar influence of the 7-dimethylamino group (compared to the unsubstituted compounds), and a more negative carboxy oxygen hydrogen-bond acceptor. For compound <b>4</b> (C<sub>21</sub>H<sub>21</sub>NO<sub>4</sub>), a stereoselective synthesis allowed preparation of the (S)-isomer which crystallized in the orthorhombic system, space group <i>P</i>2(1)2(1)2(1), with <i>a</i> = 6.7857(3) Å, <i>b</i> = 14.7140(5) Å, <i>c</i> = 17.4652(7) Å and V = 1743.81(12) Å<sup>3</sup> for 4 molecules in the cell. Compound <b>4</b> forms the <i>trans</i> cyclic hemiketal from methanol in the crystal. In CDCl<sub>3</sub> solution (298 K), <b>4</b> exists as an equilibrium mixture of three tautomers: 12.8% open form, 45.5% <i>cis</i> hemiketal and 41.7% <i>trans</i> hemiketal (coumarin forms).</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div><div><p>\u0000 Elisei Cosovan, Victor Cosovan, Daniel A. Osborne, David H. Magers, Edward J. Valente-3-Benzyl-4-hydroxy-7-dimethylaminocoumarin forms enhanced translational β-chain hydrogen-bonded arrays in the crystal</p></div></div></figure></div></div>","PeriodicalId":615,"journal":{"name":"Journal of Chemical Crystallography","volume":"54 3","pages":"274 - 284"},"PeriodicalIF":0.4,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141197005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Afifa Mushtaq, Muhammad Iqbal, Zahid Rashid, Khadija Shahid, Muhammad Nawaz Tahir, Saqib Ali
{"title":"Synthesis, Structural Elucidation and\u0000 DNA-Binding Studies of Centrosymmetric Paddlewheel Copper Carboxylate\u0000 Complexes","authors":"Afifa Mushtaq, Muhammad Iqbal, Zahid Rashid, Khadija Shahid, Muhammad Nawaz Tahir, Saqib Ali","doi":"10.1007/s10870-024-01018-1","DOIUrl":"10.1007/s10870-024-01018-1","url":null,"abstract":"<div><p>Synthesis, characterization and structural relevance of four new copper\u0000 carboxylate complexes (<b>1</b>–<b>4</b>) has been presented here. The complexes have been\u0000 synthesized by direct treatment of the substituted phenyl acetate and pyridine\u0000 ligands in aqueous medium. The complexes were stable indefinitely with excellent\u0000 yields and were characterized using spectroscopic and single crystal XRD techniques.\u0000 FTIR spectroscopy revealed the bridging bidentate coordination mode for the\u0000 carboxylate moiety in accordance to the actual structure revealed by XRD. Moreover,\u0000 UV-Visible spectroscopic and cyclic voltammetric studies helped in their\u0000 characterization and yielded signals which were typical of the copper(II) complexes.\u0000 Successfully solved single crystal XRD data showed binuclear paddlewheel structures\u0000 for all the complexes with both copper ions linked through four OCO bridges of\u0000 ortho-methoxy phenyl acetate (<b>1</b>–<b>3</b>) and ortho-methyl-meta-nitrophenyl acetate (<b>4</b>). The geometry around each copper was distorted square\u0000 pyramidal where the apical positions are occupied by meta-bromopyridine (<b>1</b>), meta-methylpyridine (<b>2</b>) and DMSO (<b>3</b> and <b>4</b>) molecules. The complexes exhibited excellent\u0000 DNA-binding activity majorly via intercalation as revealed by four experimental\u0000 techniques. This preliminary study showed that the synthesized complexes add to the\u0000 existing treasury on the paddlewheel complexes.</p><h3>The Index Abstract</h3><p>Air stable newly synthesized and purified crystalline complexes\u0000 with their preliminary structural relevance.</p>\u0000 <div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":615,"journal":{"name":"Journal of Chemical Crystallography","volume":"54 3","pages":"261 - 273"},"PeriodicalIF":0.4,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141169699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}