Convenient Chemoenzymatic Route to Optically Active β‐Aryl‐δ‐iodo‐γ‐lactones and β‐Aryl‐γ‐iodo‐δ‐lactones with the Defined Configurations of Stereogenic Centers

Abstract

Two δ‐iodo‐γ‐lactones and two γ‐iodo‐δ‐lactones substituted at the β‐position with phenyl or 4‐methylphenyl ring have been synthesized in both enantiomeric forms. The starting materials were enantiomerically enriched allyl alcohols with an (E)‐4‐phenylbut‐3‐en‐2‐ol system (ee in the range 88–99 %), which were obtained by lipase‐catalyzed transesterification. Alcohols were subjected to orthoacetate modification of the Claisen rearrangement. The high stereoselectivity of this reaction led to retention of (E)‐configuration of the double bond and complete transfer of chirality from the allyl alcohol to the benzylic position C‐3. As a result, chiral γ,δ‐unsaturated esters with retained configuration of the stereogenic center were produced. Their hydrolysis and iodolactonization afforded new enantiomers of iodolactones with high or excellent ee (97–99 %). Their configuration at C‐4 was a direct result of the configuration at C‐3 of the acid subjected to iodolactonization, whereas stereocenters at C‐5 and C‐6 were formed as a consequence of the reaction mechanism. For most of the synthesized isomers, the predicted configurations were established by X‐ray analysis. The presented chemoenzymatic pathway represents a useful strategy that can be applied in the asymmetric synthesis of variety of lactones from 4‐arylbut‐3‐en‐2‐ols.

Kinetic resolution of (E)-4-(2′,5′-dimethylphenyl)-but-3-en-2-ol and (E)-4-(benzo[d][1′,3′]dioxol-5′-yl)-but-3-en-2-ol through lipase-catalyzed transesterification

“…As a consequence, the configuration of slower reacting (À)-enantiomer of alcohol 6 obtained directly as a product of enzymatic resolution was assigned as (S). These findings are in accordance with our earlier results of the resolution of structurally related 4-arylbut-3-en-2-ols 21 and confirm the enantiopreference of CAL-B toward the (R)-enantiomers in the transesterification of this type of allyl alcohols. This enantiopreference is consistent with the known Kazlauskas' rule 41 which suggests that in the case of most lipases, the enantiorecognition between enantiomeric secondary alcohols is due to the sizes of the two substituents at the stereogenic center (Scheme 5).…”

“…20 Taking into account the influence of the configurations of the stereogenic centers on the biological properties of compounds, we have also developed a convenient chemoenzymatic pathway leading to iodolactones in both enantiomerically enriched forms. 21 Our strategy was based on the kinetic resolution of racemic 4-arylbut-3-en-2-ols by lipase-catalyzed transesterification. Previous investigations concerned the resolution of alcohols with unsubstituted or p-substituted phenyl ring.…”

Synthesis, Characterization, Cytotoxicity, and Antibacterial Properties of trans‐γ‐Halo‐δ‐lactones

“…Numerous methods for the preparation and modification of halogenolactones have been reported in the literature . In our previous work, we presented the synthesis pathways and cytotoxic properties of iodine and hydroxylactones against the tumor cell lines HL‐60, U‐2 OS and D ‐17 .…”

The Synthesis of Diamidediallylcalix[4]arene Derivatives as Ligand for Bromide Anion

“…The structures of all molecules were confirmed by 1 H, 13 C NMR and mass-spectrometry. According to these data two molecules of alkylating agent were added.…”

“…[1][2][3][4] One of the main aspects of this multi-disciplinary field of chemistry is the design and creation of unusual compounds based on these receptors and sensors for biological and inorganic cation and anion. [5][6][7][8] It is known that compounds containing allyl group are good starting materials for polymerization reaction [9][10][11][12] and chiral molecules receiving, [13][14][15] but there are only few examples of such reactions in supramolecular chemistry. [16,17] So, calixarene bearing allyl group is a promising molecule for design of various host compounds.…”