Garlicinals A−D: Bioactive Organosulfur α,β-Unsaturated Aldehydes from Garlic (Allium sativum L.) Hydrolate

Abstract

Four sulfur-derived compounds, garlicinals A–D (1–4), were isolated from the garlic (Allium sativum) bulb hydrolate. The structural elucidation of 1–4 was achieved with the help of HRMS and 1D and 2D NMR. All of these compounds are characterized by an α,β-unsaturated aldehyde in their structure. Noteworthy, this structural motif is unique in garlic-derived compounds, which would convert them into a new family of garlic-derived organosulfur compounds. A synthetic path to these compounds is proposed. Garlicinals A–C showed potent fungicidal activity against plant pathogens (Aspergillus niger and Botrytis cinerea). Furthermore, 1–4 were active against the nematode Meloidogyne javanica.