221677-48-1Relevant academic research and scientific papers
Novel synthesis of stagonolide-F, putaminoxin and aspinolide-A
Kamal, Ahmed,Reddy, Papagari Venkat,Balakrishna, Moku,Prabhakar, Singaraboina
, p. 143 - 149 (2013/01/10)
Novel synthesis of putaminoxin, stagonolide-F and aspinolide-A have been achieved by utilizing (S) and (R)- malic acid. The key feature of the synthetic strategy includes Horner-Wittig olefination, double bond reduction and Steglich esterification. Olefinic acid for putaminoxin and stagonolide-F was prepared from (S)-malic acid whereas olefinic acid for aspinolide-A was prepared from (R)-malic acid and olefinic alcohols for putaminoxin, stagonolide-F and aspinolide-A were prepared by using Brown's asymmetric allylboration.
Towards EPC-syntheses of the structural class of cochleamycins and macquarimicins. Part 3: EPC-syntheses of the β-keto lactone subunits and first attempts towards the syntheses of the pentacyclic antibiotics of this group
Chrobok,G?ssinger,Grünberger,K?hlig,White,Wuggenig
, p. 8336 - 8350 (2008/02/05)
Practical EPC-syntheses of δ-substituted-β-keto δ-lactones, subunits of the cochleamycins and macquarimicins, are presented. In consequence Tietze's tandem reaction is employed to combine δ-allyl-β-keto δ-lactone with a hydrindene derivative, the second subunit of these acetogenic antibiotics. Model reactions for the final oxidative radical tandem cyclization reveal that the electrophilic radical cyclizes exclusively in exo-trig fashion. However, with the intended precursor of macquarimicin C allylic hydrogen abstraction thwarted the oxidative radical tandem cyclization.
The first total synthesis of (-) and (+)-2-hydroxy-24-oxooctacosanolide using an effective lactonization
Shiina, Isamu,Kikuchi, Takaaki,Sasaki, Akane
, p. 4955 - 4958 (2007/10/03)
(Chemical Equation Presented) An effective method for the total synthesis of 2-hydroxy-24-oxooctacosanolide, a defensive salivary secretion of the African termite Pseudacanthotermes spiniger, has been developed. The key lactonization to form a 29-membered ring lactone core is performed using 2-methyl-6- nitrobenzoic anhydride with a catalytic amount of 4-(dimethylamino)pyridine N-oxide.
Study on fungitoxic 3-amino-2-piperidinone-containing lipids: Total syntheses of cepaciamides A and B
Toshima, Hiroaki,Maru, Kazuko,Saito, Masatoshi,Ichihara, Akitami
, p. 939 - 942 (2007/10/03)
Total syntheses of cepaciamides A and B were accomplished. In the preparation of two fatty acid segments, (S)-malic acid was used as a chiral source to introduce (2S)-configuration. A known chiral cyclopropane derivative was introduced in the segment of cepaciamide A. The formation of (Z)-olefin in the segment of cepaciamide B was achieved by means of partial reduction of the acetylenic bond. Estexification between fatty acid segments and amide segment with DCC/DMAP and subsequent oxidative deprotection of the MPM group with CAN gave cepaciamides.
Total syntheses of cepaciamides A and B, novel fungitoxic 3-amino-2- piperidinone-containing lipids produced by Pseudomonas cepacia D-202
Toshima, Hiroaki,Maru, Kazuko,Saito, Masatoshi,Ichihara, Akitami
, p. 5793 - 5808 (2007/10/03)
Total syntheses of cepaciamides A and B were accomplished. (R)-3-Amino- 2-piperidinone was obtained via cyclization of (R)-ornithine. The common amide-linked fatty acid was synthesized via Sharpless AD as the key step. Amide-formation was achieved with DEPC. In the preparation of two fatty acid segments, (S)-malic acid was used as the chiral source to introduce (2S)- configuration. A known chiral cyclopropane derivative was introduced in the segment of cepaciamide A. The formation of (Z)-olefin in the segment of cepaciamide B was achieved by means of partial reduction of the acetylenic bond. Esterification between the fatty acid-segments and the amide-segment with DCC/DMAP and subsequent oxidative deprotection of the MPM group with CAN gave cepaciamides.
