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α,β‐Unsaturated compounds are one of the most important functional compounds. Due to their unique property and versatile utility, they usually occur as the key intermediates for the synthesis of pharmaceuticals and biological materials. Thus, their synthesis has attracted more attentions than before. The early approaches to α,β‐unsaturated compounds are mainly about transition‐metal‐free methods, such as halogenation‐dehydrohalogenation methods and strong oxidants methods (organosulfur, organoselenium, benzoquinone). Subsequently, palladium and the other transition‐metals catalyzed dehydrogenation of carbonyl compounds appeared respectively. In this review, transition‐metal‐catalyzed α,β‐dehydrogenation is discussed, which is categorized by functional groups. [ABSTRACT FROM AUTHOR]

Abstract The EFSA Panel on Food Additives and Flavourings was requested to evaluate the genotoxic potential of flavouring substances from subgroup 2.2 of FGE.19 in the Flavouring Group Evaluation 208 Revision 3 (FGE.208Rev3). In FGE.208Rev1, the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF) evaluated genotoxicity studies on the representative substance p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117], which was found to be genotoxic in vivo. The Panel concluded that there was a potential safety concern for the nine substances in this FGE that were all represented by [FL‐no: 05.177]. Consequently, substance [FL‐no: 05.117], as well as four substances ([FL‐no: 05.121, 09.272, 09.899 and 09.900]), no longer supported by industry were deleted from the Union List. In FGE.208Rev2, the Panel assessed genotoxicity studies submitted on five flavouring substances [FL‐no: 02.060, 02.091, 05.106, 09.278 and 09.302] and concluded that the concern for genotoxicity could be ruled out for these substances, except from myrtenal [FL‐no: 05.106] for which the available data were considered equivocal. Thus, industry provided additional genotoxicity studies (a bacterial reverse mutation assay and a combined in vivo bone marrow erythrocytes micronucleus test and Comet assay in liver and duodenum) for this substance which were evaluated in the present opinion, FGE.208Rev3. Based on these new data, the Panel concluded that the concern for genotoxicity could be ruled out for myrtenal [FL‐no: 05.106]. Subsequently, this substance can be evaluated through the Procedure.

Abstract The EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF) was requested to evaluate the genotoxic potential of flavouring substances from subgroup 2.2 of FGE.19 in the Flavouring Group Evaluation 208 Revision 2 (FGE.208Rev2). In FGE.208Rev1, the CEF Panel evaluated genotoxicity studies on p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117], the representative substance for FGE.19 subgroup 2.2. The Comet assay performed in liver showed a positive result, and therefore, the Panel concluded that p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117] is genotoxic in vivo and that, accordingly, there is a safety concern for its use as flavouring substance. Since p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117] is representative for the nine remaining substances of subgroup 2.2 (p‐mentha‐1,8‐dien‐7‐ol [FL‐no: 02.060], myrtenol [FL‐no: 02.091], myrtenal [FL‐no: 05.106], 2,6,6‐trimethyl‐1‐cyclohexen‐1‐carboxaldehyde [FL‐no: 05.121], myrtenyl formate [FL‐no: 09.272], p‐mentha‐1,8‐dien‐7‐yl acetate [FL‐no: 09.278], myrtenyl acetate [FL‐no: 09.302], myrtenyl‐2‐methylbutyrate [FL‐no: 09.899] and myrtenyl‐3‐methylbutyrate [FL‐no: 09.900]), the Panel concluded in the previous revision of FGE.208 (FGE.208Rev1) that there is a potential safety concern for these substances. Subsequently, the industry has submitted genotoxicity studies on five substances of FGE.19 subgroup 2.2: p‐mentha‐1,8‐dien‐7‐ol [FL‐no: 02.060], myrtenol [FL‐no: 02.091], myrtenal [FL‐no: 05.106], p‐mentha‐1,8‐dien‐7‐yl acetate [FL‐no: 09.278] and myrtenyl acetate [FL‐no: 09.302], which are evaluated in the present revision of FGE.208 (FGE.208Rev2). The Panel concluded that the concern for genotoxicity could be ruled out for p‐mentha‐1,8‐dien‐7‐ol [FL‐no: 02.060], myrtenol [FL‐no: 02.091], p‐mentha‐1,8‐dien‐7‐yl acetate [FL‐no: 09.278] and myrtenyl acetate [FL‐no: 09.302], which will be evaluated through the Procedure. Genotoxicity data on myrtenal [FL‐no: 05.106] were considered equivocal, therefore, it cannot be evaluated through the Procedure, presently. p‐Mentha‐1,8‐dien‐7‐al [FL‐no: 05.117] and four substances not supported by industry (2,6,6‐trimethyl‐1‐cyclohexen‐1‐carboxaldehyde [FL‐no: 05.121], myrtenyl formate [FL‐no: 09.272], myrtenyl‐2‐methylbutyrate [FL‐no: 09.899] and myrtenyl‐3‐methylbutyrate [FL‐no: 09.900]) have been deleted from the Union List.

A series of 31 chalcones were synthesized and evaluated for anti-proliferative activity against the human cervical cancer cell lines (HeLa and SiHa). Compound 19, (E)-1-(2,4-dihydroxyphenyl)-3-(4-(dimethylamino) phenyl)-2-methylprop-2-en-1-one was found to be an effective anti-proliferative agent in HeLa and SiHa cells (IC = 0.035 μM). Compound 19 increased the percentage of apoptosis in a dose-dependent manner, as measured by Annexin V-FITC (fluorescein isothiocyanate)/(propidium iodide) PI staining. Molecular modeling studies of compound 19 showed that the most potent structure was docked at the yeast 20 S proteasome binding site (Protein Data Bank code-3E47) and was stabilized in the cavity by various hydrophobic and hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

The EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF) was requested to evaluate the genotoxic potential of flavouring substances from subgroup 2.2 of FGE.19 in the Flavouring Group Evaluation 208 Revision 2 (FGE.208Rev2). In FGE.208Rev1, the CEF Panel evaluated genotoxicity studies on p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117], the representative substance for FGE.19 subgroup 2.2. The Comet assay performed in liver showed a positive result, and therefore, the Panel concluded that p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117] is genotoxic in vivo and that, accordingly, there is a safety concern for its use as flavouring substance. Since p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117] is representative for the nine remaining substances of subgroup 2.2 (p‐mentha‐1,8‐dien‐7‐ol [FL‐no: 02.060], myrtenol [FL‐no: 02.091], myrtenal [FL‐no: 05.106], 2,6,6‐trimethyl‐1‐cyclohexen‐1‐carboxaldehyde [FL‐no: 05.121], myrtenyl formate [FL‐no: 09.272], p‐mentha‐1,8‐dien‐7‐yl acetate [FL‐no: 09.278], myrtenyl acetate [FL‐no: 09.302], myrtenyl‐2‐methylbutyrate [FL‐no: 09.899] and myrtenyl‐3‐methylbutyrate [FL‐no: 09.900]), the Panel concluded in the previous revision of FGE.208 (FGE.208Rev1) that there is a potential safety concern for these substances. Subsequently, the industry has submitted genotoxicity studies on five substances of FGE.19 subgroup 2.2: p‐mentha‐1,8‐dien‐7‐ol [FL‐no: 02.060], myrtenol [FL‐no: 02.091], myrtenal [FL‐no: 05.106], p‐mentha‐1,8‐dien‐7‐yl acetate [FL‐no: 09.278] and myrtenyl acetate [FL‐no: 09.302], which are evaluated in the present revision of FGE.208 (FGE.208Rev2). The Panel concluded that the concern for genotoxicity could be ruled out for p‐mentha‐1,8‐dien‐7‐ol [FL‐no: 02.060], myrtenol [FL‐no: 02.091], p‐mentha‐1,8‐dien‐7‐yl acetate [FL‐no: 09.278] and myrtenyl acetate [FL‐no: 09.302], which will be evaluated through the Procedure. Genotoxicity data on myrtenal [FL‐no: 05.106] were considered equivocal, therefore, it cannot be evaluated through the Procedure, presently. p‐Mentha‐1,8‐dien‐7‐al [FL‐no: 05.117] and four substances not supported by industry (2,6,6‐trimethyl‐1‐cyclohexen‐1‐carboxaldehyde [FL‐no: 05.121], myrtenyl formate [FL‐no: 09.272], myrtenyl‐2‐methylbutyrate [FL‐no: 09.899] and myrtenyl‐3‐methylbutyrate [FL‐no: 09.900]) have been deleted from the Union List. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Transition metal free approach is compatible with aromatic/heteroaromatic vinyl carboxylic acid. • Mild reaction condition for synthesis of vinyl chloride. • Simple Cinnamic acids is the starting material. • Applicable to gram-scale synthesis. Abstract While continuing our research on Hunsdiecker reaction, we came across an interesting application of bleach, sodium hypochlorite (NaOCl) for decarboxylative chlorination reaction. The reaction is easily scaled up to 10 mmol. The reaction has good tolerance towards wide variety of functional groups. The reaction has mild conditions and gave relatively high chemical yield of the desired product. [ABSTRACT FROM AUTHOR]

The combinations of N-methyl- p-toluenesulfonamide/NBS and N-ethyl- p-toluenesulfonamide/NBS were found to be good nitrogen/halogen resources for the aminohalogenation of α,β-unsaturated ketones in the presence of Ni(OAc)2 as the catalyst for the synthesis of vicinal haloamino ketone derivatives. The introduction of N-alkyl groups to the nitrogen resources resulted in excellent regio- and stereoselectivity for both electron-donating and electron-withdrawing group-attached unsaturated ketone substrates. The structure of the resulting products has been unambiguously confirmed by X-ray crystal structure analysis. [ABSTRACT FROM AUTHOR]

The EFSA Panel on Food Additives and Flavourings was requested to evaluate the genotoxic potential of flavouring substances from subgroup 2.2 of FGE.19 in the Flavouring Group Evaluation 208 Revision 3 (FGE.208Rev3). In FGE.208Rev1, the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF) evaluated genotoxicity studies on the representative substance p‐mentha‐1,8‐dien‐7‐al [FL‐no: 05.117], which was found to be genotoxic in vivo. The Panel concluded that there was a potential safety concern for the nine substances in this FGE that were all represented by [FL‐no: 05.177]. Consequently, substance [FL‐no: 05.117], as well as four substances ([FL‐no: 05.121, 09.272, 09.899 and 09.900]), no longer supported by industry were deleted from the Union List. In FGE.208Rev2, the Panel assessed genotoxicity studies submitted on five flavouring substances [FL‐no: 02.060, 02.091, 05.106, 09.278 and 09.302] and concluded that the concern for genotoxicity could be ruled out for these substances, except from myrtenal [FL‐no: 05.106] for which the available data were considered equivocal. Thus, industry provided additional genotoxicity studies (a bacterial reverse mutation assay and a combined in vivo bone marrow erythrocytes micronucleus test and Comet assay in liver and duodenum) for this substance which were evaluated in the present opinion, FGE.208Rev3. Based on these new data, the Panel concluded that the concern for genotoxicity could be ruled out for myrtenal [FL‐no: 05.106]. Subsequently, this substance can be evaluated through the Procedure. [ABSTRACT FROM AUTHOR]