Synthetic studies toward pondaplin: total synthesis of pondaplin analogues

Meroterpenoids produced by fungi

“…1 The prefix mero-(from Greek merus) means 'part, partial or fragment' 2 and, therefore, a number of secondary metabolites can be described as meroterpenoids. 3 Cytokinins, e.g., 1 and 2, 4 phenylpropanoid compounds containing isoprenoid side chains, e.g., 3-6, 5,6 and alkaloids such as anticancer drugs vincristine 7 and vinblastine 8 3 are also included in this class of compounds.…”

Macrocyclization Using RCM Reactions. Synthesis of Simple Metacyclophanes and Synthetic Efforts toward Platycarynol, a 15-Membered Aromatic Ether

“…Natural Product Communications Vol. 11 (8) 2016 1141 1 H NMR:  1.6-1.7 (2H, m), 2.13 (1H, dt, J = 13.8, 7.7 Hz), 2.23 (1H, m), 2.56 (1H, m), 2.64 (1H, m), 3.37 (2H, d, J = 6.6), 3.60 (1H, m), 3.828 (3H, s), 3.834 (3H, s), 5.10 (4H, m), 5.78 (1H, m), 5.99 (1H, ddt, J = 17, 10, 6.6 Hz), 6.6-6.8 (4H, m), 6.88 (2H s). 13 C NMR:  31.1 (CH 2 ), 38.3 (CH 2 ), 39.9 (CH 2 ), 42.0 (CH 2 ), 55.8 (CH 3 ), 56.0 (CH 3 ), 69.7 (CH), 112.4 (CH), 112.7 (CH), 115.8 (CH 2 ), 118.2 (CH 2 ), 118.6 (CH 2 x 2), 120.5 (CH), 123.…”

“…Two benzene rings might have a considerable repulsive effect to put them apart from each other. [8][9][10][11]. Except for the case of compound 23 (Figure 9), both olefin ends are not very far from each other in each case (Figs.…”

“…Many successful cyclization reactions have been reported and utilized for the synthesis of natural products [7]. Recently, a 13-membered paracyclophane, dihydropondaplin, was synthesized, but the RCM reaction for this molecule had failed [8]. A 23-membered pyrone derivative was prepared by the RCM reaction [9].…”

Metátese de olefinas aplicada ao fechamento de anéis: uma ferramenta poderosa para a síntese de macrociclos naturais

“…Além disso, a aplicação da reação de metátese na síntese de compostos macrocíclicos tensionados pode mostrar-se particularmente delicada e, até mesmo conduzir a impasses, como no caso da pondaplina (uma ansa-macrolactona tensa de 13 membros isolada de folhas de Annona glabra). As tentativas de RCM para fechar o sistema [9]-paraciclofano desta molécula por Bressy e Piva 87 , assim como as de Yadav e colaboradores 88 , falharam. Contudo, o acúmulo dos exemplos de sucessos e, eventualmente, os de fracassos, permite hoje uma melhor previsão dos fatores determinantes para o bom andamento das reações de macro-ciclização.…”