Synthesis of 7-(β-D-Glucopyranosyl)-6-Thiotheophylline and 7-(α-D-Arabinopyranosyl)-6-Thiotheopwlline. Conformational Study of the Peracetyl Derivatives.

Abstract

The synthesis of two 7-glycosyl-6-thiotheophylline nucleosides where the sugar moieties are β-D-glucose (1b) and α-D-arabinose (2b) is reported. The syn-anti equilibrium of the peracetyl derivatives was studied by the line-shape and the ¹H-NMR nOe methods, and molecular mechanics analysis.     

1RS-7DS.7DL小麦-黑麦小片段易位系的鉴定

黑麦(Secale cereale L., RR)是改良普通小麦(Triticum aestivum L., AABBDD)的重要基因资源,将黑麦优异基因转移到普通小麦中,是小麦品种改良的有效途经之一。文章将四川地方品种蓬安白麦子(T. aestivum L., AABBDD) 与秦岭黑麦(S. cereale cv. Qinling, RR)杂交,染色体自动加倍获得八倍体小黑麦CD-13(AABBDDRR);通过顺序FISH和GISH分析,发现该八倍体小黑麦1RS端部与7DS的端部发生相互易位,是一个携带1RS-7DS.7DL小麦-黑麦小片段易位染色体的八倍体小黑麦。利用八倍体小黑麦CD-13与四川推广小麦品种川麦42杂交、连续自交,获得包含60个株系的F₅群体;对F₅群体的58个株系进行GISH和FISH分析发现,其中13个株系含有1RS-7DS.7DL小片段易位染色体。在这13个株系中,株系811染色体数目为2n=6x=42,是稳定的1RS-7DS.7DL小片段易位系;并且1RS特异分子标记和醇溶蛋白分析表明,1RS-7DS.7DL易位染色体1RS小片段的断裂点位于分子标记IB267-IAG95之间,不包含编码黑麦碱蛋白的Sec-1位点;同时1RS-7DS.7DL小片段易位系的千粒重与川麦42相当,远远高于八倍体小黑麦CD-13,对千粒重无负作用。因此,1RS-7DS.7DL小麦-黑麦小片段易位系可作为进一步深入研究1RS小片段上的优异基因及其遗传效应的重要材料。     

Polymethylene Derivatives of Nucleic Bases with ω-Functional Groups: IV. [7-(2-Oxocyclohexyl)-7-oxoheptyl]purines

New polymethylene nucleoside analogues with a β-dioxo function in the ω-position of their hydro-carbon chain, [7-(2-oxocyclohexyl)-7-oxoheptyl]purines, were synthesized, and their physicochemical properties were studied.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 3, 2005, pp. 288–294.Original Russian Text Copyright © 2005 by Kritzyn, Vepsalainen, Komissarov.For communication III, see [1].