50468-21-8Relevant academic research and scientific papers
An Enantiospecific Synthesis of Monic Acid C
Kuroda, Chiaki,Theramongkol, Parinya,Engebrecht, Jeffrey R.,White, James D.
, p. 956 - 958 (1986)
Monic acid C (2) has been prepared in optically pure form from dihydropyran, thus affording a route to the naturally occurring pseudomonic acids A and C.
Total Synthesis of Geldanamycin
Zhang, Zhi,Li, Yunfeng,Zhang, Rentao,Yu, Xiaoming
, p. 15063 - 15075 (2021/11/01)
The total synthesis of geldanamycin, a well-known polyketide that exhibited potent anticancer activity by inhibiting Hsp90, was finished in 26 long linear steps with 2.65% overall yield. High convergency of the synthesis was achieved by the disconnection between C12 and C13 that gives C5-C12 and C13-C21 fragments as major building blocks. The use of an alkynyl ketone as the precursor of the C5-C12 fragment enabled a reagent-controlled establishment of C7 chirality and a highly flexible substituent exchange at C8, making the synthetic route suitable for deep-seated structural modifications on geldanamycin.
Metathesis at an Implausible Site: A Formal Total Synthesis of Rhizoxin D
Karier, Pol,Ungeheuer, Felix,Ahlers, Andreas,Anderl, Felix,Wille, Christian,Fürstner, Alois
supporting information, p. 248 - 253 (2018/12/13)
The new approach to the anticancer agent rhizoxin D described herein does not cohere with the conventional logic of metathesis, according to which macrocycles are best closed at a disubstituted olefinic site; rather, the trisubstituted C11?C12 alkene flanked by an allylic -OH group served as the pivot point for synthesis. This motif was attained in good yield and excellent selectivity by a sequence of alkyne metathesis, trans-hydrostannation and cross coupling. Because the exact same substructure is prominently featured in numerous other natural products, the underpinning strategy, though unusual, might bear more general relevance.
Asymmetric epoxidation of α,β-unsaturated aldehydes catalyzed by a spiro-pyrrolidine-derived organocatalyst
Xu, Ming-Hui,Tu, Yong-Qiang,Tian, Jin-Miao,Zhang, Fu-Min,Wang, Shao-Hua,Zhang, Shi-Heng,Zhang, Xiao-Ming
supporting information, p. 294 - 300 (2017/03/01)
The asymmetric epoxidation of α,β-unsaturated aldehydes, catalyzed by a spiro-pyrrolidine (SPD)-derived organocatalyst, has been accomplished with good diastereoselectivities (up to dr >20:1) and with high to excellent enantioselectivities (up to 99% ee).
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.
Structural revision of (+)-uprolide F diacetate confirmed by asymmetric total synthesis
Zhu, Liangyu,Tong, Rongbiao
, p. 1966 - 1969 (2015/04/27)
A new structure for the cytotoxic cembranolide uprolide F diacetate (UFD) was proposed, and an enantioselective total synthesis was accomplished to confirm that our revised structure correctly represented the natural UFD and its absolute configuration. Ou
Multigram synthesis of 1-O-acetyl-3-O-(4-methoxybenzyl)-4-N-(9-fluorenylmethoxycarbonyl)-4-N-methyl-l-pyrrolosamine
Burk, Matthew,Wilson, Nolan,Herzon, Seth B.
supporting information, p. 3231 - 3234 (2015/02/19)
The synthesis of 1-O-acetyl-3-O-(4-methoxybenzyl)-4-N-(9-fluorenylmethoxycarbonyl)-4-N-methyl-l-pyrrolosamine (7), which constitutes a protected form of the N,N-dimethyl-l-pyrrolosamine residues found within the antiproliferative bacterial metabolites (-)
Studies on the Claisen rearrangements in the indolo[2,3-b]quinoline system
Voute, Nicholas,Philp, Douglas,Slawin, Alexandra M. Z.,Westwood, Nicholas J.
supporting information; scheme or table, p. 442 - 450 (2010/02/16)
A study of the effect of substrate structure on a Claisen-aza-Cope reaction is presented including a rationalisation of the reaction outcome using DFT calculations. An asymmetric version of the reaction is also described that is of relevance to a proposed
Exploration of chiral induction on epoxides in lipase-catalyzed epoxidation of alkenes using (2R,3S,4R,5S)-(-)-2,3:4,6-di-O-isopropylidiene-2-keto-l-gulonic acid monohydrate
Sarma, Kuladip,Goswami, Amrit,Goswami, Bhabesh C.
experimental part, p. 1295 - 1300 (2009/10/17)
Epoxidation of alkenes by peracid, generated in situ from (2R,3S,4R,5S)-(-)-2,3:4,6-di-O-isopropylidiene-2-keto-l-gulonic acid monohydrate [(-)-DIKGA] and hydrogen peroxide by lipase catalysis induces chirality on the product epoxides with moderate to good enantioselectivity (35-71%). Alkoxy/aralkyloxy styrenes however did not undergo any epoxidation. (R)-(+)-4-Hydroxy styrene-7,8-oxide was formed and isolated with moderate enantiomeric excess (57%) but was found to have poor stability.
Development and application of versatile bis-hydroxamic acids for catalytic asymmetric oxidation
Barlan, Allan U.,Zhang, Wei,Yamamoto, Hisashi
, p. 6075 - 6087 (2008/02/03)
In this article, we describe the development and preliminary results of our new designed C2-symmetric bis-hydroxamic acid (BHA) ligands and the application of the new ligands for vanadium-catalyzed asymmetric epoxidation of allylic alcohols as well as homoallylic alcohols. From this success we demonstrate the versatile nature of BHA in the molybdenum catalyzed asymmetric oxidation of unfunctionalized olefins and sulfides.
