Fig. 1. Formula scheme of major dextruxin derivatives.

Fig. 2. HPLC–DAD chromatograms (210 nm) of (A) the M. anisopliae culture broth and the extracts obtained by liquid–liquid partition (B) with acetonitrile (ACN) or (C) dichloromethane (DCM). Separations were performed on a Zorbax SB-C18 column (150 mm × 2.0 mm, particle size 3.5 μm) using a water–acetonitrile gradient (t = 0 min 5% ACN; t = 6 min 50% ACN; t = 8 min 98% ACN; t = 12 min 98% ACN, flow rate 0.3 ml/min). The separation system was kept at room temperature and the injection volume was 2 μl.

Fig. 3. Fractions of apolar Sephadex LH-20 chromatography; weights against fraction numbers. Pooled fractions CF 1–CF 4 are shown in grey.

Fig. 4. HPLC–DAD chromatograms (210 nm) of the major combined fractions (CF 1 and CF 2) obtained from apolar Sephadex LH-20 chromatography. Separations were performed on a Zorbax SB-C18 column (150 mm × 2.0 mm, particle size 3.5 μm) using a water–acetonitrile gradient (t = 0 min 30% ACN; t = 4 min 98% ACN; t = 5.3 min 98% ACN; t = 5.4 min 30% ACN, flow rate 0.3 ml/min) The separation system was kept at room temperature and the injection volume was 2 μl.

Fig. 5. Fractions of HSCCC separation of CF1; weights against faction numbers. Pooled analyte fractions are shown in grey.

Partition coefficients K for dtx E (K_E), dtx A (K_A), dtx B (K_B) and total partition coefficient K_ABE of the solvent systems 1–20 tested during HSCCC-optimisation-phase.