# Morita–Baylis–Hillman modifications on hydroformylated (R)-limonene

## TL;DR

This paper describes the synthesis of new Morita–Baylis–Hillman adducts from (R)-limonene and their preliminary antitumor activity.

## Contribution

The paper introduces two new terpene-derived MBH adducts with antiproliferative potential.

## Key findings

- MBH adducts from methyl acrylate and acrylonitrile were synthesized with yields of 32% and 95%, respectively.
- The ester adduct showed promising antiproliferative activity against HT-29, PC-3, HeLa, and HACAT cell lines.
- Modest antiprotozoal and antimicrobial activity was observed in biological screening.

## Abstract

We report the sequential hydroformylation of (R)-limonene followed by Morita–Baylis–Hillman (MBH) coupling to give two new MBH adducts derived from methyl acrylate (adduct 1, 32% isolated yield) and acrylonitrile (adduct 2, 95% isolated yield). The compounds were characterized by 1H- and 13C-NMR, IR spectroscopy and elemental analysis. Biological screening against protozoa, bacteria, fungi and human cell lines revealed modest antiprotozoal and antimicrobial activity, and the ester adduct (adduct 1) showed the most promising antiproliferative activity (CC50 values: HT-29 = 211.4 ± 49.1 μg ml−1; PC-3 = 48.0 ± 2.6 μg ml−1; HeLa = 37.9 ± 6.7 μg ml−1; HACAT = 53.3 ± 3.1 μg ml−1). These results introduce a new set of terpene-derived MBH adducts with preliminary antitumoural potential and encourage further optimization and mechanistic studies.