在約1458年之後奧魯貝就沒有再被提及 ,有一段時間没有大公的名字留傳下來;热那亚文献只提到“狄奧多羅的領主和他的兄弟們”(dominus Tedori et fratres ejus)。[3]在1465年,以撒大公被記載,他可能是奧魯貝的儿子,因此可能早於約1458年登位。[3]面对日益严重的鄂圖曼威脅,他在卡法与热那亚人「和解」,并将他的妹妹玛丽亚·阿萨尼娜·帕莱奥洛吉娜(英语:Maria of Mangup)嫁给了摩達維亞的统治者斯特凡大帝。[3]然而,他在晚年越來越親鄂圖曼的立場導致1475年他的兄弟亞歷山大在斯特凡的支持下將他推翻。[3]但要拯救狄奧多羅為時已晚:1475年12月,在征服克里米亞海岸的其他基督教據點後,鄂圖曼人在圍攻了三個月後占領了這座城市。亞歷山大大公和他的家人被俘虏到君士坦丁堡,他在那裡被斬首。他的兒子被迫皈依伊斯蘭教,他的妻子和女兒成为蘇丹後宮的一部分。[3]
^Khvalkov (2017). "Thus it was the base for all the Genoese wars with the principality of Theodoro, a Greek state on the foothill of the Crimean Mountains."
^Vasiliev 1936: "Finally, at the end of December 1475, Theodoro-Mankup, or as the report of the authorities of Ragusa says, ‘the community Alexa which in common speech was called Thodoreza (Thodoriza) ,’ surrendered, on condition that the lives of the Prince and his people, as well as their property, should be spared."
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Pritsak, Omeljan. : Alexander Kazhdan.Editors list列表中的|first1=缺少|last1= (帮助); 缺少或|title=为空 (帮助)
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