X-ray and NMR studies of a cyclophosphamide-like molecule, cis-2-oxo-2-dimethylamino-3-phenyl-5-tert-butyl-1,3,2-oxazaphosphorinane. Twist conformation in both solid phase and in solution

Conformations of Saturated Six-Membered-Ring Phosphorus Heterocycles Syntheses and X-Ray Crystal Structures of Two 2-(Dimethylamino)-2-Oxo-3-Aryl-5,5-Dimethyl-1,3,2-Oxazaphosphorinanes

“…By comparison, for a series of 1,3,2-dioxaphosphorinanes, 6, with -OR = 2-nitrophenoxy, 3-nitro- These substituents, for both the 1,3,2-dioxaphosphorinanes and the tetrahydropyranyl acetals, span a much wider range of electronic character than do p-F and p-NMe,. We shall attempt to obtain X-ray quality crystals for the analog of 1 and 2 for which X = NO,.…”

cis- und trans-2,9-Diphenoxy-1,3,8,10-tetraaza-2λ5,9λ5-diphosphatricyclo[8.4.0.03,8]tetradecan-2,9-disulfid, C20H26N4O2P2S2

“…Mean bond distances for cis and [trans] isomers: N-N 1.413 (7) (Spagna & Vaciago, 1978;Nelsen, Hollinsed & Calabrese, 1977;Katritzky, Baker, Camalli, Spagna & Vaciago, 1980). Die Struktur derartiger Ringverbindungen ist auch wegen ihrer Verwandtschaft zu 'cyclophosphamidiihnlichen' Molekrilen interessant, einer Verbindungsklasse, die in der Anti-Krebs-Therapie eine wichtige Rolle spielt und in der in neuerer Zeit ebenfalls Beispiele ffir stabile Twistkonformationen ges~ittigter Sechsringe gefunden worden sind (Bajwa, Bentrude, Pantaleo, Newton & Hargis, 1979;Bajwa, Chandrasekaran, Hatgis, Sopchik, Blatter & Bentrude, 1982 (Engelhardt & Hartl, 1976;Engelhardt & Viertel, 1982a,b;Engelhardt, Bringer & Viertel, 1984;.…”

Structure of 2-chloro-5-methyl-6-phenyl-3-(p-tolyl)perhydro-1,3,2λ5-oxazaphosphorine 2-oxide, C17H19ClNO2P

“…As part of a programme of X-ray studies on the structure and conformation of oxazaphosphorine ring systems, which are known to be clinically useful anticancer drugs, the title compound was prepared (Sahasrabudhe & Tilak, 1983 recent studies have shown that the 1,3,2-oxazaphosphorine ring undergoes conformational changes due to steric and electronic influences on P (Bajwa, Bentrude, Pantaleo, Newton & Hargis, 1979;Gorenstein & Rowell, 1979;Gorenstein, Rowell & Findlay, 1980;Maryanoff, Hutchins & Maryanoff, 1979) and to the substituents on ring N (Chandrasekharan & Bentrude, 1980;Bajwa, Chandrasekharan, Hargis, Sopchik, Blatter & Bentrude, 1982). (1) 3514 (7) 3460 (7) 2843 (7) 3.6 (2) 0 (2) 5006 (7) 2634 (9) 2102 (8) 3.6 (1) N (3) 3218 (8) 3725 (9) 782 (8) 3.2 (1) C (4) 2041 (10) 4148 (11) 644 (11) 2-5 (1) C (5) 2031 (9) 4782 (11) 1726 (10) 2.6 (2) C (6) 2375 (10) 3955 (12) 2733 (11) 2.9 (2) C (7) 4300 (12) 2982 (13) -3288 (11) 4.6 (3) C (8) 806 (11) 5250 (13) 1552 (10) 4.2 (3) C(l') 2505 (11) 4555 (11) 3805 (10) 3.2 (2) C(2') 1656 (13) 4411 (14) 4278 (12) 2.8 (2) C(Y)…”