The stereomers of hept-6-ene-2,5-diol derivatives were conceived as useful chiral intermediates and were synthesized starting from sulcatol using two lipase-catalyzed acylation reactions as the key steps. The versatility of the intermediates was demonstrated by converting them to the titled tetrahydropyran, macrolide, and macrodiolide compounds using standard synthetic protocols.

The refluxing of chloroacetamide derivatives with n-butyl imidazole resulted in their corresponding salt of composition 1-(n-butyl)-3-N-(2-Ar)acetamido-1, 3-imidazolium chloride (Ar = furylmethyl (1a); phenylmethyl (1b)). The latter salt on treatment with DBU followed by the addition of chalcogen atom resulted into a compoundSimilarly, the reaction of the imidazolium salts with, excess K2CO3 and NiCl2.6H2Ofurylmethyl (3a); phenylmethyl (3b)). The latter complexes have also been isolated by using Ni(II) phosphine precursors [NiCl2(P-P)] (P-P = PPh3, dppf). The molecular structure of [(1-(nbutyl)-3-N-(2-furylmethyl)acetamido-1, 3-imidazol-3-ylidine)]2Ni and [(1-(n-butyl)-3-N-(2-phenylmethyl)acetamido-1, 3-imidazol-3-ylidine)]2Ni were established by single crystal X-ray diffraction analysis. The catalytic property of complex 3a and 3b for cross coupling reactions has been studied.

An efficient synthesis of the Alpinia off icinarum-derived diarylheptanoids, viz., enantiomers of a β-hydroxyketone (1) and an α,β-unsaturated ketone (2) was developed starting from commercially available eugenol. Among these, compound 2 showed a superior antiproliferative effect against human breast adenocarcinoma MCF-7 cells. Besides reducing clonogenic cell survival, compound 2 dose-dependently increased the sub G1 cell population and arrested the G2-phase of the cell cycle, as revealed by flow cytometry. Mechanistically, compound 2 acts as an intracellular pro-oxidant by generating copious amounts of reactive oxygen species. Compound 2 also induced both loss of mitochondrial membrane potential (MMP) as well as lysosomal membrane permeabilization (LMP) in the MCF-7 cells. The impaired mitochondrial and lysosomal functions due to reactive oxygen species (ROS)-generation by compound 2 may contribute to its apoptotic property.

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The macrolide antibiotic (−)-A26771B is synthesized using lipase catalyzed reactions as the key steps.