Total synthesis of noricumazole B establishes d-arabinose as glycan unit

Preparation of an advanced intermediate for the synthesis of leustroducsins and phoslactomycins by heterocycloaddition

“…However, model studies for coupling revealed the incompatibility of the lactone function; therefore, it was reduced with DIBAL-H then transformed into 19 by a one pot acetalization-desilylation procedure (91:9 mixture of diastereomers) [17]. Hydrozirconation followed by treatment with iodine furnished the target vinyl iodide 20 (Scheme 6); iodination with NIS, as previously described [29], gave lower yields.…”

Synthesis of isochromanone containing natural products from myxobacteria

“…The reported total synthesis of noricumazole B ( 12 ) 45 is based on the noricumazole A ( 11 ) synthesis and is depicted in Scheme 20. Compound 144 was taken through 5 steps to give acid 145 which was converted into vinyl iodide 146 .…”

Muscarine, imidazole, oxazole and thiazole alkaloids

“…A concise total synthesis of noricumazole B 328 has established its complete aglycon structure, identical to that of noricumazole A, and recognized the glycan moiety as an a-D-arabino furanose unit. 215 By a combination of high eld NMR studies, molecular modelling, and chemical derivatization, the relative and absolute congurations of leupyrrin A 1 329 and B 1 330, the potent anti-fungal agents from the myxobacterium Sorangium cellulosum, have been fully assigned. 216 Subsequently, the aforementioned assignment was ultimately validated by an enantioselective total synthesis of leupyrrin A 1 .…”