Enzyme-catalyzed enantiomeric resolution of N-Boc-proline as the key-step in an expeditious route towards RAMP

Kurokawa, Masayuki; Shindo, Takeyuki; Suzuki, Masumi; Nakajima, Nobuyoshi; Ishihara, Kohji; Sugai, Takeshi

doi:10.1016/s0957-4166(03)00210-6

Cited by 21 publications

(8 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…IR (neat, cm -1 ) ν max 2976, 2881, 1747, 1695, 1392, 1365, 1199, 1157, 1119, 1088, 1033, 999, 974, 922, 888, 858, 772. Identical NMR and IR spectra were observed previously by Kurokawa et al…”

Section: Methodssupporting

confidence: 77%

Synthesis and Spin-Trapping Properties of a New Spirolactonyl Nitrone

et al. 2008

View full text Add to dashboard Cite

Spin trapping using electron paramagnetic resonance (EPR) spectroscopy is commonly employed for the identification of transient radicals in chemical and biological systems. A spirolactonyl-nitrone with rigid H-bond acceptor, 7-oxa-1-azaspiro[4.4]non-1-en-6-one 1-oxide, CPCOMPO, has been synthesized and characterized, and its spin-trapping properties were investigated. The rate of formation of CPCOMPO-O2H was determined using competition kinetics between the superoxide/hydroperoxyl radical (O2*-/HO2*) trapping by CPCOMPO and the spontaneous dismutation of this radical in aqueous media. The rate constant of 60 M-1.s-1 is the highest rate constant thus far observed at neutral pH for any nitrones using the kinetic method employed. Decay kinetics were also experimentally investigated for CPCOMPO-O2H. The effect of rigid H-bond acceptor on the stability of the CPCOMPO-O2H were computationally rationalized and compared to that of EMPO-O2H, which has flexible H-bond acceptor, and results show the need of a "loose" H-bond acceptor for improved adduct stability.

show abstract

Section: Methodssupporting

confidence: 77%

Synthesis and Spin-Trapping Properties of a New Spirolactonyl Nitrone

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Enantiomerically pure alcohols 5p – r with potentially labile stereocenters at the α-position were applicable under the reaction conditions without compromising the optical purity of the products 6p – r . The integrity of the stereocenters in the products was proven by reducing aldehydes 6p – r back to the starting alcohol and analysis of the corresponding Mosher esters of 5p and 5r , or the benzoate of 5q (see the Supporting Information). However, amino alcohols, such as N -Boc-prolinol 5q or phenylalaninol 5r , reacted slowly and the conversion stopped after some time, even though they were oxidized previously by 1…”

mentioning

confidence: 99%

Anaerobic Nitroxide-Catalyzed Oxidation of Alcohols Using the NO⁺/NO· Redox Pair

Holan

Jahn

2013

Org. Lett.

View full text Add to dashboard Cite

A new method for alcohol oxidation using TEMPO or AZADO in conjunction with BF3·OEt2 or LiBF4 as precatalysts and tert-butyl nitrite as a stoichiometric oxidant has been developed. The system is based on a NO(+)/NO· pair for nitroxide reoxidation under anaerobic conditions. This allows the simple, high-yielding conversion of various achiral and chiral alcohols to carbonyl compounds without epimerization and no formation of nonvolatile byproducts.

show abstract

“…Total amount of 2e was 118 mg (95%). 9 Other urea derivatives were prepared similarly and characterized by comparison their IR, 1 H NMR and/or melting points with the reported data. 5c,6e,6g,9…”

Section: Methodsmentioning

confidence: 99%

An Efficient Hydration of Cyanamides to Substituted Ureas with Acetaldoxime as an Effective Water Surrogate

Kim¹,

Park²,

Kim³

2011

Bulletin of the Korean Chemical Society

View full text Add to dashboard Cite

Enzyme-catalyzed enantiomeric resolution of N-Boc-proline as the key-step in an expeditious route towards RAMP

Cited by 21 publications

References 58 publications

Synthesis and Spin-Trapping Properties of a New Spirolactonyl Nitrone

Synthesis and Spin-Trapping Properties of a New Spirolactonyl Nitrone

Anaerobic Nitroxide-Catalyzed Oxidation of Alcohols Using the NO⁺/NO· Redox Pair

An Efficient Hydration of Cyanamides to Substituted Ureas with Acetaldoxime as an Effective Water Surrogate

Contact Info

Product

Resources

About

Enzyme-catalyzed enantiomeric resolution of N-Boc-proline as the key-step in an expeditious route towards RAMP

Cited by 21 publications

References 58 publications

Synthesis and Spin-Trapping Properties of a New Spirolactonyl Nitrone

Synthesis and Spin-Trapping Properties of a New Spirolactonyl Nitrone

Anaerobic Nitroxide-Catalyzed Oxidation of Alcohols Using the NO+/NO· Redox Pair

An Efficient Hydration of Cyanamides to Substituted Ureas with Acetaldoxime as an Effective Water Surrogate

Contact Info

Product

Resources

About

Anaerobic Nitroxide-Catalyzed Oxidation of Alcohols Using the NO⁺/NO· Redox Pair