an agilent 1200 series 
 hplc system equipped with a diode array detector and a phenomenex 
 c18 column ( 5 m , 250  21.2 mm ) was used for 
 preparative hplc . for hplc - ms analysis ,
an agilent hplc system equipped 
 with a diode array detector and a 6130 series quadrupole mass spectrometer 
 was used with a phenomenex c18 ( 5 m , 100  
 4.6 mm ) column .
the following gradient was used for hplc - ms analysis : 
 05 min , isocratic 10% ch3cn + 0.1% formic acid ; 
 525 min , linear gradient from 10% ch3cn + 0.1% 
 formic acid to 100% ch3cn + 0.1% formic acid .
nmr spectra 
 were recorded in cd3od ( for compounds 14 ) or cd2cl2 ( for compound 5 ) at 600 mhz and referenced to the internal solvent peak at h 3.30 and c 49.0 or h 5.32 
 and c 53.8 , respectively .
high - resolution mass spectrometry 
 ( hr - ms ) was performed at the university of illinois urbana 
an ant colony of a. dentigerum was collected from 
 pipeline road , panama , on may 29 , 2008 , and placed in a sterile petri 
 dish with moist cotton . after allowing the nest to stabilize for a 
 few days , the pseudonocardia symbiont from this colony 
 was isolated directly from the mesoternal lobe of a worker by scraping 
 bacteria off the cuticle of the ant using a sterile scalpel and plating 
 on chitin media following the methods of caldera and currie , and identified 
 as pseudonocardia sp .
ec080529 - 01 
 were grown on solid isp-2 medium ( per liter : yeast extract , 4 g ; malt 
 extract , 10 g ; glucose , 4 g ) in 12 petri plates ( 150  20 mm , 
 1.2 l total ) for 7 d at 30 c .
the solid agar was cut into small 
 cubes and soaked in etoac ( 1.2 l ) overnight .
the etoac was filtered 
 and dried in vacuo to give the crude etoac extract . 

the solid agar was re - extracted overnight with meoh ( 1.2 l ) , and the 
 meoh was filtered and dried in vacuo to give the 
 crude meoh extract .
the crude etoac extract was dissolved in 90% meoh  h2o ( 20 ml ) and passed through a c18 column , eluting 
 with additional 90% meoh 
the eluent from this column was diluted with 
 h2o to give a final meoh concentration of 60% .
this solution 
 was passed through another c18 column and washed with additional 
 60% meoh 
h2o fraction was purified by preparative 
 hplc using the following gradient : 05 min , isocratic 20% ch3cn  h2o ; 560 min , linear gradient 
 from 20% ch3cn 
the 100% meoh fraction from 
 this c18 column was purified by preparative hplc using 
 the following gradient : 010 min , isocratic 50% ch3cn  h2o ; 1060 min , linear gradient from 
 50% ch3cn 
the crude meoh extract was dissolved 
 in h2o and passed through an hp-20 column .
the hp-20 column 
 was washed with water to remove polar components , and the compounds 
 of interest were then eluted with 100% meoh .
the eluent from this column was diluted with h2o to give a final meoh concentration of 30% .
this solution was passed 
 through another c18 column and washed with additional 30% 
 meoh 
the 100% meoh fraction 
 from this c18 column was purified by reversed - phase hplc 
 using the following gradient : 010 min , isocratic 10% ch3cn  h2o + 0.1% formic acid ; 1060 
 min linear gradient from 10% ch3cn  h2o + 0.1% formic acid to 100% ch3cn + 0.1% formic acid 
 to give pure 1 ( 2.0 mg ) , 2 ( 0.9 mg ) , and 3 ( 1.8 mg )
. colorless solid 
 ( 2.0 mg ) ; [ ]d 11 ( c 0.02 , meoh ) ; uv ( meoh ) max ( log  ) 310 nm 
 ( 3.11 ) , 279 ( sh ) , 271 nm ( 3.59 ) ; h nmr ( 600 mhz , cd3od ) and c nmr ( 150 mhz , cd3od ) , see 
 table 1 ; ( + ) -hresi m / z 497.1438 [ m + h ] ( calcd for c26h25o10 , 497.1448 ) .
yellow solid ( 0.9 
 mg ) ; [ ]d 2 ( c 0.02 , meoh ) ; uv ( meoh ) max ( log  ) 377 nm 
 ( 3.52 ) , 305 nm ( 3.87 ) ; h nmr ( 600 mhz , cd3od ) 
 and c nmr ( 150 mhz , cd3od ) , see table 1 ; ( + ) -hresi m / z 495.1295 [ m + h ] ( calcd for c26h23o10 , 495.1291 ) .
orange solid ( 1.8 
 mg ) ; [ ]d 3 ( c 0.09 , meoh ) ; uv ( meoh ) max ( log  ) 403 nm 
 ( 3.53 ) , 314 nm ( 3.96 ) ; h nmr ( 600 mhz , cd3od ) 
 and c nmr ( 150 mhz , cd3od ) see table 1 ; ( + ) -hresi m / z 511.1229 ( calcd for c26h23o11 , 
 511.1240 ) .
the appropriate test organism was 
 grown in a 5 ml culture overnight in either lb medium ( for e. coli and b. subtilis ) or ypd medium 
 ( for c. albicans and s. cerevisiae ) at 30 c . in each case , the overnight culture was diluted 
 with additional sterile medium ( lb or ypd ) to an od600 of 
 0.01 .
compounds 15 were dissolved 
 in dmso to give a concentration of 5 mg / ml and 2-fold serially diluted . 
 these solutions ( 1 l )
were added to the wells of a 96-well 
 plate , followed by the diluted culture of the test organism ( 99 l ) 
 to give a final compound concentration ranging from 50 to 0.1 g / ml . 
 the cultures were allowed to grow for 24 h at 30 c before the 
 od600 was measured using a plate reader .
the mic was defined 
 as the lowest concentration that gave less than 5% of the maximum 
 od600 .
dynemicin a was used as a positive control and gave mic values against e. coli , b. subtilis , c. albicans , and s. cerevisiae of 313 , 0.16 , 156 , and 156 ng / ml , 
 respectively .
compounds were tested for activity 
 against hepg2 human hepatoma cells ( atcc ) that were maintained in 
 dmem ( invitrogen ) , 10% fbs ( sigma ) , and 1% antibiotic 
antimycotic 
 ( invitrogen ) in a standard tissue culture incubator ( 37 c , 5% 
 co2 ) . for assays , compounds 15 ( in dmso )
the final concentration of dmso was 1% , and compounds 
 varied from 0 to 50 g / ml .
cells were incubated with the compounds 
 for 2 days at 37 c , and then liver cell viability was assessed 
 with celltiter - glo ( promega ) .
the relative signal intensity of each 
 sample was evaluated with an envision ( perkinelmer ) system .
liver - stage p. berghei assays were performed using a luciferase - expressing 
 sporozoite strain of p. berghei anka .
parasites were 
 obtained from dissection of plasmodium - infected anopheles stephensi mosquitoes ( new york university langone 
 medical center insectary ) .
malaria parasites ( 4000 sporozoites ) were 
 used to infect hepg2 cells ( 15  000 cells ) in a 384-well plate 
 in the presence of compounds 15 in 
 triplicate .
the final concentration of dmso was 1% , and compounds 
 varied from 0 to 50 g / ml . cells
were incubated with the compounds 
 for 2 days at 37 c , and then relative parasite load was determined 
 after addition of bright - glo ( promega ) .
data analysis for hepg2 toxicity 
 and liver - stage malaria activity was carried out using graphpad prism , 
 and curves were fit with a standard inhibition dose 
all statistical results 
 are the mean ic50 value averaged from two independent experiments . 

atovaquone was used as a positive control and gave an ic50 in blood stage assays of 0.3 nm .
 three new members of the angucycline class of antibiotics , 
 pseudonocardones 
 a  c ( 13 ) , along with the 
 known antibiotics 6-deoxy-8-o - methylrabelomycin ( 4 ) and x-14881 e ( 5 ) have been isolated from 
 the culture of a pseudonocardia strain associated 
 with the fungus - growing ant apterostigma dentigerum . 
 compounds 4 and 5 showed antibiotic activity 
 against bacillus subtilis 3610 and liver - stage plasmodium berghei , while 13 were inactive or only weakly active in a variety of biological assays . 
 
 compound 5 also showed moderate cytotoxicity against 
 hepg2 cells . 
Experimental Section