First synthesis of lycoperdic acid

An Efficient Transformation of Cyclic Ene-carbamates into .OMEGA.-(N-Formylamino)carboxylic Acids by Ruthenium Tetroxide Oxidation

“…Similarly, the free amino acid (13) was obtained from the 3-silyloxy derivative (12b) in 85% yield. 13 was identical to the authentic sample, 28) and was the key compound for the formal synthesis of L-carnitine (15).…”

“…The first example of this type of reaction was described by Desai and co-workers, 5) who reported one case that attempted the cleavage of a CϭC bond in steroidal enamines. Torii and co-workers 6) revealed the procedure for the RuO 4 oxidative cleavage of enolic olefins including two six-membered nitrogen-containing heterocyles that afforded the carbonyl compounds under the conditions using the substrate in a suspension of CCl 4 and H 2 O in the presence of RuO 2 · xH 2 O and NaIO 4 .On the other hand, we have been working on the transformation of cyclic [7][8][9] and acyclic [10][11][12] N-acyl amines into the corresponding lactams and imides including the natural products [13][14][15][16][17] by the RuO 4 oxidation. The double layer oxidation method using a catalytic amount of RuO 2 hydrate, an excess of a NaIO 4 aqueous solution and ethyl acetate system was established for these purposes in our laboratory.…”

“…On the other hand, we have been working on the transformation of cyclic [7][8][9] and acyclic [10][11][12] N-acyl amines into the corresponding lactams and imides including the natural products [13][14][15][16][17] by the RuO 4 oxidation. The double layer oxidation method using a catalytic amount of RuO 2 hydrate, an excess of a NaIO 4 aqueous solution and ethyl acetate system was established for these purposes in our laboratory.…”

The Chemoselective Reduction of Isoxazolineγ-Lactams Through Iminium Aza-Diels-Alder Reactions: A Short-Cut Synthesis of Aminols as Valuable Intermediates towards Nucleoside Derivatives

“…The protocol needs only a catalytic amount of the expensive RuO 2 ·H 2 O (10–20% mol.) in the presence of 2.5 equivalents (with respect to the substrate to be oxidized) of sodium periodate as oxidant in order to regenerate the oxidizing species RuO 4 at the highest oxidation state after the end of the catalytic cycle [ 40 – 42 ]. Typically, RuO 2 ·H 2 O is added to a solution of NaIO 4 in water in inert atmosphere and left under stirring for 30 minutes.…”

Construction of spirolactones with concomitant formation of the fused quaternary centre – application to the synthesis of natural products

“…This methodology was employed in the first synthesis of lycoperdic acid (35) (Scheme 13), 35 a non-proteinogenic a-amino acid isolated in 1978 from the mushroom Lycoperdon perlatum. 36 To date, no biological activity has been reported for this natural product.…”