following examples can be made without exceeding the spirit or scope of the invention as will be evident to those skilled in the art individual isomeric forms can be obtained by separation of mixtures thereof in conventional manner for example in the case of diasteroisomeric isomers chromatographic separation may be employed compound names were generated with acd version 8 and intermediates and reagent names used in the examples were generated with software such as chem bio draw ultra version 12 0 or auto nom 2000 from mdl isis draw 2 5 sp1 in general characterization of the compounds is performed according to the following methods nmr spectra are recorded on 300 and or 600 mhz varian and acquired at room temperature chemical shifts are given in ppm referenced either to internal tms or to the solvent signal all the reagents solvents catalysts for which the synthesis is not described are purchased from chemical vendors such as sigma aldrich fluka bio blocks combi blocks tci vwr lancaster oakwood trans world chemical alfa ascentscientific llc fisher maybridge frontier matrix ukrorgsynth toronto ryan scientific silicycle anaspec syn chem chem impex mic scientific ltd however some known intermediates were prepared according to published procedures usually the compounds of the invention were purified by column chromatography auto column on an teledyne isco combiflash with a silica column unless noted otherwise s m h d second minute hour day nh 3 ammonia ch 3 cn acetonitrile psi pound per square inch dcm dichloromethane dmf n n dimethylformamide naoh sodium hydroxide meoh methanol cd 3 od deuterated methanol nh 3 ammonia hcl hydrochloric acid na 2 so 4 sodium sulfate rt room temperature dmf dimethylformamide mgso 4 magnesium sulfate etoac ethyl acetate cdcl 3 deuterated chloroform dmso.