Menthofurolactone: a new p‐menthane lactone in Mentha piperita L.: analysis, synthesis and olfactory properties

Abstract

3,6-Dimethyl-4,5,6,7-tetrahydro-benzo[b]-furan-2(3H)-one (D menthofurolactone), first reported as a by-product in the oxidation of menthofuran and hitherto unknown in nature, is shown to be naturally occurring in Mentha piperita L. essential oil. In addition to a description of its synthesis and organoleptic properties, the key role of menthofurolactone in the flavour profile of peppermint oil is demonstrated by mint oil analysis and olfactory studies.

TiCl4‐Et3N‐mediated one‐step synthesis of γ‐alkylidenebutenolides from ketones: Application to natural product synthesis

“…13 C NMR (100 MHz, CDCl 3 ) δ 171. 2, 151.2, 149.6, 124.0, 111.1, 28.1, 26.7, 22.7, 22.6, 14.1, 13.9, 8.8 7,149.3,148.2,119.9,114.2,31.1,29.9,21.7,21.3,8.5. HRMS (EI) 6, 151.7, 133.83, 131.0, 129.6, 128.0, 127.9, 126.9, 125.3, 123.5, 106.6, 38.1, 16.4 4.5 | Procedure for probing the mechanism of the cascade TiCl 4 (1.0 M in DCM, 1.5 mL, 1.5 mmol) and Et 3 N (0.42 mL, 3.0 mmol) were successively added to a stirred solution of 1i (178.3 mg, 1.0 mmol) in dry DCM (1.0 mL) at −78 C under an argon atmosphere, followed by stirring for 0.5 h. To the reaction mixture, 2a (2.0 mmol) was added.…”

(R)‐Tonkafuranone and related compounds: Improved synthesis, stereochemical purity in nature, and bioactivities of the pure enantiomers

“…Over many years, a considerable plethora of lactone‐based flavour compounds have been isolated from a broad variety of plants. Several of these substances have been shown to be essential flavour constituents of peppermint oil …”

“…The compound was first described as the dehydrogenated autoxidation product of menthofurane by Woodward and Eastman in 1950 . Thus, it is not surprising that 1a was also found in peppermint oil ( Mentha piperita L.), providing a coumaric and coconut flavour and a mint and tenacious smell …”

Lactones 38: Synthesis and odoriferous properties of p‐menthane lactones

“…The best‐known mintlactones 1 , 2a–5a and 6 were isolated from the essential oils of several Mentha species . In 1997, Iwabuchi reported the isolation of enantiomeric (+)‐3‐hydroxymintlactone ( 2b ), (+)‐mintlactone ( 3b ), (−)‐isomintlactone ( 4b ) and (−)‐2,3‐didehydromintlactone ( 5b ) from the oils of woods Bursera graveolens .…”

“…The best-known mintlactones 1, 2a-5a and 6 were isolated from the essential oils of several Mentha species. [1][2][3][4][5][6][7] In 1997, Iwabuchi reported the isolation of enantiomeric (+)-3hydroxymintlactone (2b), (+)-mintlactone (3b), (À)-isomintlactone (4b) and (À)-2,3-didehydromintlactone (5b) from the oils of woods Bursera graveolens. [8][9][10] The synthesis of all the eight possible diastereoisomers of the completely saturated analogues of (À)-mintlactone (3a) and (+)-isomintlactone (4a) was reported by Gaudin.…”