The transaction of purchase an asset from its related party is capital in nature and payment is debited to Fixed Asset account.
Therefore the question of reporting this transaction under clause 18 of Form 3CD under head "Payments to Relatives under section 40A(2)(b) does not arise as same is not claimed as a deduiction from profits & gains of buisness or profession.
However the allowability of depreciation on such fixed Assets used in the assessee company may arise.
Amounts not deductible in respect of payment to Relatives [Sec. 40A(2)]
As per the provisions of this section any payment made by an assessee to any of his ‘Relatives’ in respect of any expenditure is disallowable to the extent it is considered excessive, or unreasonable, having regard to the market value of Goods or Services or Facilities etc.
Here the following definitions need to be considered for better understanding:
‘Relative’ is defined to include Husband, Wife, Brother, Sister or any other Lineal Ascendant or Descendant; and
‘Substantial Interest’ is defined as a situation wherein a person is the beneficial owner of at least 20% or more Equity Voting Power (in case of Company) or is entitled to 20% or more of the profits. (in any other case).
The extent of disallowablity is to be decided by the assessee himself and proportionate expenditure be disallowed at the time of filing of his Self Assessment Tax u/s 139 of the Income Tax Act.
Thus, I don't think that the transaction falls under the category of payments to relatives u/s.40A(2)(b).