Exhibit 1
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Joint Filing Agreement
The undersigned hereby agree that the statement on Schedule 13D filed by
the undersigned with respect to the Common Stock of Synaptic Pharmaceutical
Corporation is, and any amendment thereto signed by each of the undersigned
shall be, filed on behalf of each undersigned pursuant to and in accordance with
the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as
amended.
Dated: August 9, 2001 WARBURG PINCUS PRIVATE EQUITY VIII, L.P.
By: Warburg, ▇▇▇▇▇▇ & Co.,
General Partner
By: /s/ ▇▇▇▇▇ ▇▇▇▇▇▇▇
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Name: ▇▇▇▇▇ ▇▇▇▇▇▇▇
Title: Attorney in Fact
Dated: August 9, 2001 WARBURG, ▇▇▇▇▇▇ & CO.
By: /s/ ▇▇▇▇▇ ▇▇▇▇▇▇▇
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Name: ▇▇▇▇▇ ▇▇▇▇▇▇▇
Title: Attorney in Fact
Dated: ▇▇▇▇▇▇ ▇, ▇▇▇▇ ▇▇▇▇▇▇▇ PINCUS LLC
By: /s/ ▇▇▇▇▇ ▇▇▇▇▇▇▇
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Name: ▇▇▇▇▇ ▇▇▇▇▇▇▇
Title: Vice President
