Crystal structure of 3-(4-fluorophenyl)-4-hydroxyfuran-2(5H)-one, C10H7FO3

Abstract

C 10 H 7 FO 3 ,monoclinic, P12 1 /c1(no. 14), a =7.584(2) Å, b =8.863(2) Å, c =12.707(3) Å, b =90.64(1)°, V =854.1 Å 3 , Z =4,R gt(F) =0.041, wRref(F 2 ) =0.107, T =296 K. Source of materialAs olution of 2-ethoxy-2-oxoethyl 2-(4-fluorophenyl)-acetate (0.96 g, 4mmol) in dry THF was added dropwise to asuspension of NaH in dry THF in an ice cold bath. The stirring was maintained at room temperature for 5h.Water was added and the solution was extracted twice with ethyl ether. The aqueous phase was cooled to 0°Cand then acidified with concentrated hydrochloric acid to give asolid precipitate. The title compound was crystallized from ethanol-water (2:1, v/v)t og ive the colorless blockshaped crystals suitable for single-crystal structure determination. DiscussionCompounds with g-butyrolactone-core (furanone) show diverse biological activities such as antitumor and anti-inflammatory activity [1][2][3]. It is reported that butalactin exhibits moderate antibacterial activity against Gram-positive bacteria [4]. Based on this findings, some derivatives of g-butyrolactone (5-alkoxy-4-aminofuran-2(5H)-one) showing good antibacterial activity against multiresistant Staphylococcus aureus were reported [5]. Recently, we focused our efforts to synthesize enamines with gbutyrolactone-core for antibacterial activity screening. In the title crystal structure, the bond length d(C7-C10) = 1.346(2) Å is in the range of atypical double bond (1.32 -1.38 Å), and the title compound was therefore identified as afuran-2(5H)-one not afuran-2(3H)-one. Because C9 attaches to adouble bond, s-p hyperconjugation occurring between C9-H9A (H9B) and C7-C10 slightly shortens C9-C10 bond from about 1.53 to 1.490(2) Å.C10-O3 (1.316(2) Å)bond length is shorter than the standard C-Osingle bond (1.41 -1.44 Å), but longer than C-O double bond (1.19 -1.23 Å). This clearly indicated that an sp 3 orbital of O3 is conjugated with the p molecular orbital of C7=C10 double bond, which was supported by the small torsion angle (-1.5(2)°)ofC1-C7-C10-O3. The stereochemistry of the double bond in lactone ring was assigned as (E)-configuration (figure, top). The butyrolactone moiety makes ad ihedral angle of 17.86(6)°with the 4-fluorophenyl group. In the title compound, the two independent hydrogen bonds generate at wo-dimensional layer of edge-fused centrosymmetric rings running parallel to (100), with R 2 2 (8) rings built from pairs of C-H···Fhydrogen bonds centred at (0,3n/2 +1,-1n/2), where n represents an integer, and with the R 6 6 (44) rings built from pairs of C-H···Fa nd O-H···Oh ydrogen bonds centred at (0,3n/2+1, 1n/2), where n again represents an integer (figure, bottom). The resulted layer has azigzag pattern in the cross section, running along the [010] direction. In al ayer, each R 6 6 (44) ring runs through by other two R 6 6 (44) rings which are from other two layers, respectively, and these layers (three) therefore interweave each other to form al ayered tablet. The title ompound extends further to its final three-dimensional network through ...

Structure and Antibacterial Activity of 3-(3,4-Dimethoxyphenyl)furan-2(5H)-ones

“…In the center lactone moiety, C8-C11 and C8-O1 are typical double bonds with bond length of 1.350(2) and 1.210(2) Å respectively, while bond distances of others are followed in the range of typical single bonds ( Table 3). The center five-member ring is therefore identified as a furan-2(5H)-one, which are consistent with the analogues previously reported [11,12]. An sp 3 orbital of O2, O3, O4 or O5 is conjugated with the attached double bond, which shortens the bond length of C-O from about 1.43 Å [15,16] to 1.36 Å .…”

“…The furan-2(5H)-one motif and the attached benzene ring (3,4-dimethoxy benzene ring) are nearly co-planar, making a dihedral angle of 0.860(69)8. This is consistent with other 4-O-analogues [12,13], and is quite different with the 4-N-analogues [11]. In comparison with C7-C8 (1.43-1.47 Å ), the bond distance of C7-C10 (1.33-1.37 Å ) significantly decreased, causing an increase in steric strain between 4-substituent and 3-benzene ring.…”

“…Compounds 1 and 2 were obtained according to the procedure previously described [11,12], which were further treated as follows to produce compounds 3-9 (Scheme 2; Table 2). A mixture of compound 2 (0.5 mmol) and triethylamine (225 lL, 1.5 mmol) was dissolved in 15 mL of dry DMF and heated to 50°C.…”

Crystal structure of 3-(4-bromophenyl)-4-(4-chloro-phenylamino)furan-2(5H)-one, C16H11BrClNO2

“…Fore xample,s omed erivatives of gbutyrolactone (5-alkoxy-4-aminofuran-2(5H)-one) showing good antibacterial activity against multiresistant Staphylococcus aureus were reported [2].4-Alkylamino or 4-arylamino derivatives of 3-arylfuran-2(5H)-one are potent inhibitors against tyrosyl-tRNA synthetase (TyrRS) [1,3], one of the aminoacyltRNA synthetases(aaRSs). In the title compound, the bond C7-C10 (1.375(4) Å) was assigned as ad ouble bond [4,5], and the title compound was thereforeidentified as afuran-2(5H)-one, notafuran-2(3H)-one. Butyrolactone moiety and the attached amino group (H1,N 1, C10 and C11)a re nearly co-planar with ad ihedral angle of 5.2(2)°, indicating theconjugation of p orbitalofN1withthe p molecular orbital of C7-C10,which shortens the bond distance of C10-N1.…”