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The metabolic profile of Streptomyces sp. strain C34, isolated from the Chilean hyper-arid Atacama Desert soil, is dependent on the culture media used for its growth. The application of an OSMAC approach on this strain using a range of cultivation media resulted in the isolation and identification of three new compounds from the rare class of 22-membered macrolactone polyketides, named chaxalactins A-C (1-3). In addition, the known compounds deferroxamine E (4), hygromycin A (5), and 5″-dihydrohygromycin A (6) were detected. The isolated compounds were characterized by NMR spectroscopy and accurate mass spectrometric analysis. Compounds 1-3 displayed strong activity against Gram-positive but weak activity Gram-negative strains tested.

Two approaches to the synthesis and structure determination of NaZnPO 4 ‚H 2 O, a new open-framework, chiral, hydrated sodium zincophosphate phase, are reported. The ordered, alternating, vertex-sharing ZnO 4 and PO 4 groups in NaZnPO 4 ‚H 2 O form a new framework topology, which includes novel 4-ring "squares" and edge-sharing helixes of 4-rings. The disordered extra-framework species (Na + , H 2 O) are located in pear-shaped cavities (12-ring diameter), interconnected through 8-rings and 6-rings. Crystal data: NaZnPO 4 ‚H 2 O (I), M r ) 201.36, hexagonal, space group P6 1 22 (No. 178), a ) 10.4797(8) Å, c ) 15.089(2) Å, V ) 1435 Å 3 , Z ) 12, R ) 5.99%, R w ) 5.29% (709 observed reflections with I > 3σ(I). NaZnPO 4 •H 2 O (II), M r ) 201.36, hexagonal, space group P6 5 22 (No. 179), a ) 10.412(2) Å, c ) 15.184(2) Å, V ) 1426 Å 3 , Z ) 12, R ) 6.90%, R w ) 8.10% (687 observed reflections with I > 4σ(I).

The structure of the low-temperature hexagonal form of SrCo03-,.is determined by Rietveld analysis of powder neutron diffraction data and identified as