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Search Results: 1 - 10 of 17 matches for " Nawong Boonnak "
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Vieillardiixanthone BThis paper is dedicated to His Majesty King Bhumibol Adulyadej of Thailand (King Rama IX) for his sustainable development of the country.
Nawong Boonnak,Suchada Chantrapromma,Hoong-Kun Fun,Chatchanok Karalai
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810007026
Abstract: The title compound [systematic name: 1,5-dihydroxy-3,6-dimethoxy-4-(2-methylbut-3-en-2-yl)-9H-xanthen-9-one], C20H20O6, is a xanthone, which was isolated from the roots of Cratoxylum formosum ssp. pruniflorum. The three rings in the molecule are approximately coplanar, with an r.m.s. deviation of 0.0372 (2) for the plane through the 14 non-H atoms. The O atoms of the two hydroxy substituents also lie close to this plane with deviations of 0.0669 (2) and 0.1122 (2) , respectively. The 1,1-dimethyl-2-propenyl substituent is in a ( )-anticlinal conformation. Intramolecular O—H...O hydrogen bonds generate S(5) and S(6) ring motifs. In the crystal, molecules are linked into infinite chains along [010] by O—H...O hydrogen bonds and weak C—H...O interactions. π–π interactions with centroid–centroid distances of 3.6172 (10) and 3.6815 (10) are also observed.
A second orthorhombic polymorph of (Z)-3-(9-anthryl)-1-(2-thienyl)prop-2-en-1-oneThis paper is dedicated to His Majesty King Bhumibol Adulyadej of Thailand (King Rama IX) for his sustainable development of the country.
Suchada Chantrapromma,Thitipone Suwunwong,Nawong Boonnak,Hoong-Kun Fun
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810000061
Abstract: The title heteroaryl chalcone, C21H14OS, is a second orthorhombic polymorph which crystallizes in the space group P212121. The structure was previously reported [Fun et al. (2009). Acta Cryst. E65, o2168-o2169] in the space group Pna21. The bond distances and angles are similar in both structures. In contrast, the overall crystal packing is different from that in the first orthorhombic Pna21 polymorph in which molecules were stacked into columns along the b axis and the thiophene units of two adjacent columns were stacked in a head to tail fashion. In the present polymorph, molecules are found to dimerize through a weak S...S interaction [3.6513 (7) ] and these dimers are arranged into sheets parallel to the bc plane. There are no classical hydrogen bonds in the packing which features short C...O [3.2832 (2)–3.6251 (9) ], C...S [3.4879 (17)–3.6251 (19) ] and S...O [2.9948 (16) ] contacts, together with C—H...π interactions. Similar contacts were found in the other polymorph.
3-O-Methyl-1-isomangostin
Nawong Boonnak,Suchada Chantrapromma,Hoong-Kun Fun
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812023409
Abstract: In the title xanthone derivative [systematic name: 9-hydroxy-5,10-dimethoxy-2,2-dimethyl-11-(3-methylbut-2-en-1-yl)-2,3,4,12-tetrahydro-1,7-dioxatetraphen-12-one], C25H28O6, the xanthone ring system is roughly planar, with an r.m.s. deviation of 0.1038 (1) . The chromane ring is in a half-chair conformation and the 3-methylbut-2-enyl substituent is axially attached with an (+)-anticlinal conformation. Two weak intramolecular C—H...O interactions generate two S(6) ring motifs. In the crystal, molecules are linked into ribbons along the c axis by O—H...O and weak C—H...O hydrogen bonds. A π–π interaction, with a centroid–centroid distance of 3.5413 (8) , is also observed.
(E)-2-[4-(Diethylamino)styryl]-1-methylpyridinium 4-methoxybenzenesulfonate monohydrate
Suchada Chantrapromma,Narissara Kaewmanee,Nawong Boonnak,Teerasak Anantapong
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812035258
Abstract: In the cation of the title compound, C18H23N2+·C7H7O4S ·H2O, one ethyl group of the diethylamino unit is disordered over two sets of sites in a 0.665 (6):0.335 (6) ratio. The styrylpyridinium unit is nearly planar, with a dihedral angle between the pyridinium and benzene rings of 4.27 (8)°. In the crystal, the anion ring is almost perpendicular to the aromatic rings of the cation; the sulfonate-substituted benzene ring forms dihedral angles of 89.60 (8) and 89.37 (8)°, respectively, with the pyridinium and benzene rings of the cation. In the crystal, the three components are linked into a three-dimensional network by O—H...O and C—H...O hydrogen bonds. π–π interactions with centroid–centroid distances of 3.6999 (9) and 3.7106 (9) are also present.
5-Amino-3-ethoxy-1,8,8-trimethyl-2-azabicyclo[2.2.2]octa-2,5-diene-4,6-dicarbonitrile
Suchada Chantrapromma,Thitipone Suwunwong,Pumsak Ruanwas,Nawong Boonnak
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812032990
Abstract: The title 2-azabicyclo[2.2.2]octa-2,5-diene derivative, C14H18N4O, crystallized out with two independent molecules with similar conformations in the asymmetric unit. In each molecule, the three six-membered rings adopt boat conformations. The molecules exist in the enamine form. In the crystal, molecules are linked by N—H...O and N—H...N hydrogen bonds into a two-dimensional network parallel to the ab plane.
Absolute configuration of xerophenone A
Hoong-Kun Fun,Cholpisut Tantapakul,Surat Laphookhieo,Nawong Boonnak
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812015267
Abstract: The title compound, C33H42O5, known as xerophenone A {systematic name: (1R,3R,4R,6S,8E,10R)-10-hydroxy-8-[hydroxy(phenyl)methylene]-4-methyl-1,6-bis(3-methylbut-2-en-1-yl)-3-(3-methylbut-3-en-1-yl)-11-oxatricyclo[4.3.1.14,10]undecane-7,9-dione} is a naturally occurring rearranged benzophenone compound which was isolated from the twigs of Garcinia propinqua. The absolute configuration was determined by refining the Flack parameter to 0.18 (16). The absolute configurations at positions 1, 3, 4, 6 and 10 of the xerophenone A are R, R, R, S and R. In the molecule, the cyclohexane-1,3-dione, tetrahydro-2H-pyran and tetrahydrofuran rings adopt twisted boat, standard chair and envelope conformations, respectively. The 3-methylbut-3-en-1-yl substituent is disordered over two sets of sites in a 0.771 (11):0.229 (11) ratio. An intramolecular O—H...O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked by O—H...O and weak C—H...O interactions into a chain along the a axis. A very weak C—H...π interaction and C...O short contact [2.989 (2) ] are also present.
2-(2,4,5-Trimethoxyphenyl)-2,3-dihydroquinolin-4(1H)-one
Suchada Chantrapromma,Pumsak Ruanwas,Nawong Boonnak,Kan Chantrapromma
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812002917
Abstract: In the title aza-flavanone, C18H19NO4, an intramolecular cyclization product of chalcone, the central heterocyclic ring is in an envelope conformation and the dihedral angle between the benzene rings is 51.03 (10)°. The methoxy groups at the ortho and para positions are slightly twisted from the benzene ring to which they are bound [C—O—C—C = 21.9 (3) and 171.93 (18)°, respectively], whereas the methoxy group at the meta position is almost coplanar [C—O—C—C = 3.5 (3)°]. In the crystal, molecules are linked by N—H...O hydrogen bonds and weak C—H...O interactions into chains along the [001] direction. Weak C—H...π interactions also occur.
(E)-2-[4-(Diethylamino)styryl]-1-ethylpyridinium iodide monohydrate
Suchada Chantrapromma,Nawong Boonnak,Narissara Kaewmanee,Ching Kheng Quah
Acta Crystallographica Section E , 2013, DOI: 10.1107/s160053681300528x
Abstract: In the title hydrated salt, C19H25N2+·I ·H2O, the 4-(diethylamino)phenyl unit of the cation is disordered over two positions in a 0.847 (3):0.153 (3) ratio. The cation is twisted, with dihedral angles between the pyridinium and benzene rings of 11.25 (13) and 10.7 (8)° for the major and minor components, respectively. In the crystal, the three components are linked into a centrosymmetric 2:2:2 unit by O—H...I and C—H...O hydrogen bonds. π–π interactions with centroid–centroid distances of 3.5065 (7)–3.790 (9) are also present.
BrasilixanthoneThis paper is dedicated to Her Royal Highness Princess Chulabhorn Walailak of Thailand on the occasion of her 53rd Birthday Anniversary which fell on July 4th, 2010.
Suchada Chantrapromma,Nawong Boonnak,Hoong-Kun Fun,Chatchanok Karalai
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810027285
Abstract: The title xanthone [systematic name: 5,13-dihydroxy-3,3,10,10-tetramethyl-3H-dipyrano[3,2-a:2′,3′-i]xanthen-14(10H)-one], C23H20O6, was isolated from the roots of Cratoxylum formosum ssp. pruniflorum. There are two molecules (A and B) in the asymmetric unit, which show chemical but not crystallographic inversion symmetry. The xanthone skeleton in both molecules is approximately planar, with an r.m.s. deviation of 0.0326 (9) for molecule A and 0.0355 (9) for molecule B from the plane through the 14 non-H atoms. The pyran rings in both molecules adopt sofa conformations. Intramolecular O—H...O hydrogen bonds generate S(5) and S(6) ring motifs. Viewed onto the bc plane, the crystal structure resembles a herringbone pattern. Stacks of molecules are stabilized by π–π interactions with centroid–centroid distances of 3.600 (5) . The crystal structure is further stabilized by weak C—H...O and C—H...π interactions.
Redetermination and absolute configuration of pruniflorone M monohydrate
Hoong-Kun Fun,Suchada Chantrapromma,Nawong Boonnak,Chatchanok Karalai
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811025177
Abstract: The title xanthone known as pruniflorone M (systematic name: (2R)-5,10-dihydroxy-2-hydroxymethyl-1,1-dimethyl-1H-furo[2,3-c]xanthen-6-one), crystallized in a monohydrate form, C18H16O6·H2O. It was isolated from the green fruits of Cratoxylum formosum ssp. pruniflorum. The structure of the title compound has been reported previously [Boonnak et al. (2010). Aust. J. Chem. 63, 1550–1556], but we report here the absolute configuration determined using Cu Kα radiation. There are two crystallograpically independent molecules in the asymmetric unit, which differ slightly in the bond angles. The hydroxymethyl substituents at position 2 of the furan rings of both pruniflorone M molecules adopt R configurations. In both molecules, the three rings of the xanthone skeleton are approximately coplanar, with an r.m.s. deviation of 0.0124 (2) for one molecule and 0.0289 (2) for the other, and the furan ring adopts an envelope conformation. In the crystal, molecules of pruniflorone M and water are linked into a two-dimensional network by O—H...O hydrogen bonds and weak C—H...O interactions. The crystal structure is further consolidated by π–π interactions with centroid–centroid distances in the range 3.5987 (13)–3.7498 (14) . Short C...C [3.378 (3) ] and O...O [2.918 (3) ] contacts are also observed.
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