Detail of "16096-97-2"

Reference

Approaches to the resolution of racemic cyclic disulfides

Approaches to the resolution of racemic cyclic disulfides. Application to an epidithiodioxopiperazine. Ottenheijm, Henricus C. J.; Herscheid, Jacobus D. M.; Nivard, Rutger J. F. (Dep. Org. Chem., Cathol. Univ. Nijmegen, Nijmegen, Neth.). J. Org. Chem., 42(5), 925-6 (English) 1977. CODEN: JOCEAH. DOCUMENT TYPE: Journal CA Section: 28 (Heterocyclic Compounds (More Than One Hetero Atom)) Section cross-reference(s): 22 Two approaches for the yet unreported chem. resoln. of a cyclic disulfide lacking a reactive handle have been described, which might be of general applicability. In a kinetically controlled, asymmetric transformation of racemic I (n = 2) into I (n = 1) with an optically active diphosphine II (R1 = Ph2P), 19% enantiomeric enriched starting material I (n = 2) was isolated. Reaction of the disulfenyl chloride II (R1 = SCl) with racemic dithiol III (n = 0) gave the diastereomeric disulfides (2S,10aS)-IV and (2R,10aR)-IV (56% yield), which could be sepd. easily by silica gel column chromatog. Conversion of these IV into the enantiomers V and VI, resp., was achieved using NaBH4 redn., followed by oxidn. 16096-97-2 and 58788-23-1 which are cas registry numbers of substances are two of reagents here. with iodine-pyridine (82% yield). The resolving agent II (R1 = SCl) was obtained in 50% yield from L-(+)-tartaric acid. The enantiomeric purity of V and VI (>90%) was detd. by 3H NMR spectroscopy using an Eu(III) chiral shift reagent, while tentative abs. configurations (V = S, VI = R) were derived from CD spectra. Both enantiomers have the same anti-reverse transcriptase activity. .