Should I capitalize a person's last name if their name starts with a lower case letter but it's the first word in the sentence? [duplicate]
If you absolutely cannot reword the sentence to put the name somewhere else, then, yes, you need to capitalize de Soya.
Sentences always need capital first letters. However, an extremely special case is a sentence beginning with a word such as iTunes. The lowercase i is allowed because the very next letter is capitalized. This creates a slight gray area in terms of where the capital letter has to be in the first word, but it's a rule nonetheless.