96930-18-6Relevant academic research and scientific papers
Asymmetric total synthesis and formal total synthesis of the antitumor sesquiterpenoid (+)-eremantholide A
Yi, Li,Hale, Karl J.
, p. 1267 - 1270 (2007)
Figure presented A new asymmetric total synthesis of (+)-eremantholide A is reported in which a Hoveyda-Grubbs ring-closing metathesis (RCM) reaction is used to assemble the nine-membered oxonin ring, and an enolate alkylation between the 3(2H)-furanone 2
Sensing remote chirality: Stereochemical determination of β-, γ-, and δ-chiral carboxylic acids
Tanasova, Marina,Anyika, Mercy,Borhan, Babak
supporting information, p. 4274 - 4278 (2015/04/14)
Determining the absolute stereochemisty of small molecules bearing remote nonfunctionalizable stereocenters is a challenging task. Presented is a solution in which appropriately substituted bis(porphyrin) tweezers are used. Complexation of a suitably derivatized β-, γ-, or δ-chiral carboxylic acid to the tweezer induces a predictable helicity of the bis(porphyrin), which is detected as a bisignate Cotton Effect (ECCD). The sign of the ECCD curve is correlated with the absolute stereochemistry of the substrate based on the derived working mnemonics in a predictable manner.
An unusual conformation of α-haloamides due to cooperative binding with zincated porphyrins
Tanasova, Marina,Yang, Qifei,Olmsted, Courtney C.,Vasileiou, Chrysoula,Li, Xiaoyong,Anyika, Mercy,Borhan, Babak
supporting information; experimental part, p. 4242 - 4253 (2011/02/25)
CD and NMR spectroscopic evidence of cooperative binding between an α-halogen atom and a carboxamide group with a zinc porphyrin leads to an unprecedented conformation for the determination of the absolute stereochemistry of α-haloamides (α-halocarboxylic acids derivatized with 1,4-phenylenediamine) through the use of exciton-coupled circular dichroism (ECCD). With the use of chiral lactams, whose rotomeric contributions are minimized, both ECCD and NMR spectroscopy demonstrate that the porphyrin favors binding to the side of the sterically more demanding halogen atom as compared to the smaller hydrogen atom. In all, the data is strongly suggestive of an unusual conformation not observed before for α-chiral amides. A mnemonic for determining the absolute stereochemistry of α-halogenated carboxylic acids is provided.
Syntheses of 20'-Deoxyvinblastine, 20'-Deoxyleurosidine, 20'-Deoxyvincovaline, 20'-epi-20'-Deoxyvincovaline, and 20'-Deoxyvincristine and Its 20'-Epimer through Racemic and Enantioselectively Generated Intermediates. New Syntheses of D/E-cis- and -trans-Ψ
Kuehne, Martin E.,Bornmann, William G.
, p. 3407 - 3420 (2007/10/02)
Vindoline (20), on reaction with chloro imine derivatives of the D-seco-D/E-trans-Ψ- and -20-epi-Ψ-vincadifformines 18 and 19, followed by cyclization and debenzylation steps, provided the natural products 20'-deoxyvinblastine (4) and 20'-deoxyleurosidine
