Abstract: Methods are provided for preparing a compound with a fused ring structure of formula (XIV) which comprises one or more reactions starting from a 21-cyano compound of formula (XVI) where typically; R1 is an amidomethylene group or an aryloxymethylene group; R5 and R8 are independently chosen from —H, —OH or —OCOCH2OH, or R5 and R8 are both keto and the ring A is a p-benzoquinone ring; R14a and R14b are both —H ozone is —H and the other is —OH, —OCH3 or —OCH2CH3, or R14a and R14b together form a keto group; and R15 and R18 are independently chosen from —H or —OH, or R5 and R8 are both keto and the ring A is a p-benzoquinone ring. In modified starting materials, the 21-cyano group can be replaced by other groups introduced using nucleophilic reagents.

Abstract: A hatch-actuating mechanism, particularly for aircraft landing gear with a lateral closing panel (1) and a secondary closing panel (4) articulated to one another, a lateral pivoting fitting (5) joined at the bottom to the lateral panel (1), couplable by lateral means of articulation (6) to a fixed structure (7), a secondary pivoting fitting (8) joined at the bottom to the secondary panel (4), a lateral actuating cylinder (10) articulated on the fixed structure and on the lateral pivoting fitting (5), an intermediate actuating cylinder (13) coupled to a first coupling point (14) between the lateral means of articulation (6) and the intermediate means of articulation (9) on the lateral pivoting fitting (5), as well as on a second coupling point (15) on the secondary pivoting fitting (8), the intermediate actuating cylinder (13) being actuatable independently from the lateral actuating cylinder (10).

Abstract: Device for facilitating the lowering of a landing gear by gravity, comprising at least on roller device (4) positioned on at least one closing panel (2) of the hatch for the landing gear in a contact area with the tire (1a) of the landing gear of an aircraft (7) on initiating its descent, the roller device (4) comprising a rigid roller device which can rotate freely about its axis (4a), and being positioned such that its axis is perpendicular to the path of the tire (1a) so that the tire will make the roller device (4) turn without sliding over it.

Abstract: Processes are provided for preparing compounds with a fused ring structure of formula (XIV). Such products include ecteinascidins and have a spiroamine-1,4-bridge. The process involving forming a 1,4 bridge using a 1-labile, 10-hydroxy, 18-protected hydroxyl, di-6,8-en-5-one fused ring compound. After formation of the 1,4 brige, C-18 protection is removed before spiroamine introduction.