... 44. BS Holla and SI Ambekar, J. Chem. Soc., Chem. ... The isoxazolidine fragment is contained in alkaloids [12, 13], terpenes [14], condensed heterocycles [15, 16], some sugar derivatives [17, 18], and antibiotics [19]. ... (There is only a review on the chemistry of isoxazolidines [20 ...