Abstract: A progesterone compound represented by the following formula (1): ##STR1## ?wherein R.sup.1 represents a C1-C23 hydrocarbon group!, and a neovascularization inhibitor containing the same as the active ingredient.The compound (1) has a potent neovascularization inhibitory effect and is hence useful in the treatment of malignant tumors, diabetic retinitis, rheumatism, etc.

Abstract: An oil seal of the type having a metallic reinforcement rig whose outer peripheral portion is oil-tightly fitted into a housing, characterized in that after the formation of fabrication of said metallic reinforcement ring, the latter is subjected to a nitriding hardening process so that its durability of a raw material of said metallic reinforcement ring; and a seal lip of formed over the inner peripheral edge portion of an annular flange portion of said metallic reinforcement ring.

Abstract: New camptothecin derivatives possessing high anti-tumor activity with slight toxicity, represented by the general formula: ##STR1## wherein R.sup.1 is a hydrogen atom, a halogen atom or an alkyl group with 1-4 carbon atoms and X is a chlorine atom or --NR.sup.2 R.sup.3 where R.sup.2 and R.sup.3 are the same or different and each represents a hydrogen atom, a substituted or unsubstituted alkyl group with 1-4 carbon atoms or a substituted or unsubstituted carbocyclic or heterocyclic group, with the proviso that when both R.sup.2 and R.sup.3 are the substituted or unsubstituted alkyl groups, they may be combined together with the nitrogen atom, to which they are bonded, to form a heterocyclic ring which may be interrupted with --O--, --S-- and/or >N--R.sup.4 in which R.sup.