Abstract: The invention concerns N-nitroso compounds having the general formula: ##STR1## wherein A is lower alkyl or halolower alkyl;B is hydrogen; lower alkenyl; lower alkynyl; 3-6 C cycloalkyl; --RSO.sub.2 NR.sup.3 R.sup.4, or lower alkyl optionally monosubstituted with lower alkoxy, or 3-6 C cycloalkyl;R is straight or branched 2-5 C alkylene, optionally monosubstituted with SO.sub.2 NR.sup.3 R.sup.4 or CONR.sup.3 R.sup.4, said alkylene always containing at least two carbon atoms separating the nitrogen atom of the urea from any SO.sub.2 NR.sup.1 R.sup.2 or SO.sub.2 NR.sup.3 R.sup.4 ;R.sup.1 and R.sup.2 are the same or different and selected from hydrogen, 5-6 C cycloalkyl, lower alkoxy, phenyl, benzyl, and straight or branched 1-6 C alkyl, optionally monosubstituted with hydroxy, lower alkoxy, SO.sub.2 NR.sup.3 R.sup.4, or CONR.sup.3 R.sup.4 ; R.sup.1 and R.sup.2 may also together form a 4-5 C alkylene; and R.sup.3 and R.sup.4 are the same or different and selected from hydrogen or lower alkyl, or R.sup.3 and R.

Abstract: This invention relates to a selective acylation process for the preparation of phenolic N-disubstituted carbamate esters of steroids, comprising reacting in an inert solvent an acylating agent being a carbamoyl halogenide, a 4-(tertiary amino)-pyridine, or a complex thereof, optionally as a part of a polymer and a steroid having at least two free hydroxy groups, where at least one is phenolic and at least one is alcoholic, optionally in the presence of an acid acceptor.

Abstract: This invention relates to an improved steroid ester synthesis in which carbodiimides and catalytic amounts of 4-(tertiary amino)-pyridines, in combination with acid catalysts, are used as condensing agents, resulting in pure, non discolored compounds in high yields.