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Previously, we reported the preparation of two crystalline 0-p-nitrobenzoyl halides of 2,6-dideoxy-D-ribo-hexopyranose (digito~ose).~ Subsequently, we were able to couple crystalline 3,4-di-O-pnitrobenzoyl-p-D-ribo-hexosyl chloride (I) with digitoxigenin to give, after removal of the protecting groups, a 2-deo~ycardenolide.~ This success prompted us to investigate the possibility of extending this direct method of synthesis of 2-deoxyglycosides to the preparation of some new 2'-deoxynucleosides as possible anticancer compounds.The extreme reactivity of the chloride I precluded any conditions involving elevated temperatures lest elimination of hydrogen chloride take place before coupling could be accomplished.Fortunately, I coupled readily with chloromercuri-6-benzamidopurine in dry dichloromethane at room temperature to give the protected nucleoside IV as semiamorphous material. Without further CH3 r purification, IV was deacylated giving crude 9-(2,6-dideoxy-~-ribo-hexopyranosyl)adenine (V), which was purified via its picrate salt and was isolated as a crystalline monohydrate. The yield of the nucleosjde V was 28% based on chloromercuri-6-benzamidopurine. Colorimetric estimation of the digotoxose content of the nucleoside V employing xanthydrol reagent gave results in excellent agreement with the calculat'ed value. A small quantity of V was hydrolyzed by means of dilute mineral acid and the resulting hydrolysis mixture was resolved by paper chromatography. This technique disclosed two components which were identified as adenine and digotoxose, respectively.Repeated attempts to couple I a t room temperature with mercury derivatives of thymine6 resulted

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