Spontaneous enrichment of one-handed helices by dissolution of quasiracemic crystals of a tetranuclear single helical complex.
نویسندگان
چکیده
The left-handed isomer of the helical complex [LZn(3)La(OAc)(3)] was spontaneously enriched from 50 : 50 to 87 : 13 when the quasiracemate crystals were dissolved. The invertible helicity of [LZn(3)La(OAc)(3)] (global chirality) helps the quasiracemate formation and the fixed point chirality of the R,R-cyclohexanediamine moiety (local chirality) effectively controls the global chirality in solution.
منابع مشابه
بررسی تمایل مجاورت اسیدهای آمینه با یکدیگر در مارپیچهای آلفا
In order to study the tendency of amino acid neighbors in helical structures, proteins with known structures were carefully analyzed. The studied helical positions: N , Ncap, N1, N2, N3, N4, M, C4, C3, C2, C1, Ccap, C and their doublet counterparts: N Ncap, NcapN1, N1N2, N2N3, N3N4, M1M2, M2M3, C4C3, C3C2, C2C1, C1Ccap, CcapC were carefully analyzed. The propensity for all amino acids i...
متن کاملConstruction of right-handed-, left-handed-, and racemic helical coordination polymers. Enantioselective recognition using chiral helical crystals.
Infinite square-tubular helices, [CuCl2(L)(S)] (L = bis(4-pyridyl)methylvinylsilane; S = Me2SO, HCONMe2), were constructed. This helical system affords three kinds of P, M crystals in Me2SO, and racemic crystals in HCONMe2. The cyclic voltammogram (CV) technique using the M-crystals is an effective tool for discerning the chirality of proline.
متن کاملA theoretical reasoning on why coordination catalysts supported on mesoporous supports produce HDPE crystalline nanofibers but not iPP crystalline nanofibers
Since 1999, when Takuzo Aida proposed the preparation of high density polyethylene (HDPE) crystalline nanofibers through polymerization of ethylene by a Cp2 TiCl2 /MCM-41 catalyst, many researchers have published various papers on different aspects of the idea. The published researches show that the endeavors to polymerize other types of alpha olefins, especially propylene, to obtain polyolefin...
متن کاملA designed protein with packing between left-handed and right-handed helices.
A common motif in protein structures is the assembly of alpha-helices. Natural alpha-helical assemblies, such as helical bundles and coiled coils, consist of multiple right-handed alpha-helices. Here we design a protein complex containing both left-handed and right-handed helices, with peptides of D- and L-amino acids, respectively. The two peptides, D-Acid and L-Base, feature hydrophobic hepta...
متن کاملThree 2D Ag(I)-framework isomers with helical structures controlled by the chirality of camphor-10-sulfonic acid.
Three 2D Ag(I)-framework isomers were constructed from enantiopure camphor-10-sulfonic acids or racemic camphor-10-sulfonic acids, together with achiral 4-aminobenzoic acids. In complex 1, (+)-camphor-10-sulfonic acids bridge the single left-handed helices that are made up of Ag ions and 4-aminobenzoic acids, generating a homochiral 2D layer. In such a structure, the interweaving of triple left...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Chemical communications
دوره 47 10 شماره
صفحات -
تاریخ انتشار 2011