Six novel lactone derivatives, cryptolaevilactones A-F (1-6), were isolated from Cryptocarya laevigata. Their unique spiro[3.5]nonane moiety by hetero [2 + 2] cyclization with monoterpene and polyketide was found for the first time in nature. Structural elucidation using various nuclear magnetic resonance (NMR) techniques revealed that 1-3 and 4-6 are diastereomers and partially established the absolute configurations.

A CH3OH–CH2Cl2 (1:1) extract (N025439) of the leaves and twigs of Cryptocarya laevigata furnished eight new compounds, 1–8. Based on extensive 1D and 2D NMR spectroscopic data examination, the new δ-lactone derivatives 1–6 are monoterpene–polyketide hybrids containing a unique spiro[3.5]­nonenyl moiety. Their trivial names, cryptolaevilactones G–L, follow those of the related known meroterpenoids cryptolaevilactones A–F. Cryptolaevilactone L (6) contains 11,12-cis-oriented substituents, while the other cryptolaevilactones contain trans-oriented groups. The structure of the linear δ-lactone 7, cryptolaevilactone M, was characterized from various spectroscopic data analysis, and the absolute configuration was determined by total synthesis through stereoselective allylation and Grubbs olefin metathesis. Compound 8 was elucidated to be an ionone derivative with a 3,4-syn-diol functionality.

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The first total synthesis of (±)-neocaryachine (1) was achieved using a radical cyclization to produce the dibenzo-9-azabicyclo[3.3.1]nonane pavine skeleton, following a Bischler-Napieralski reaction to construct an intermediate benzylisoquinoline. The resulting racemic mixture was separated by chiral column chromatography to provide pure (+)-and (−)-1.

Cryptolaevilactones (CLs) A-L, found in the leaves and twigs of Cryptocarya laevigata, are unique natural meroterpenoids with a spiro[3.5]nonane skeleton. We report the total synthesis of a simplified model compound of CLs A-C. The synthetic route included introduction of a styryl group and coupling of a lactone moiety to a spiro ring system, which was constructed by a pinacol-like rearrangement.