SHARE PURCHASE AGREEMENT

Exhibit 10.1

SHARE PURCHASE AGREEMENT

This SHARE PURCHASE AGREEMENT is made as of 3 August, 2009, by and among Alliance UniChem Group Limited, a company incorporated in England and Wales with registered number 00546864 having its registered address at 2 The Heights, Brooklands, Weybridge, Surrey, KT13 ONY (the “ Purchaser ”), and BMP Sunstone Corporation (formerly known as Beijing Med-Pharm Corporation), a Delaware corporation having its principal office at 600 W. Germantown Pike, Suite 400, Plymouth Meeting, PA 19462 (the “ Seller ,” and, together with the Purchaser, the “ Parties ”).

BACKGROUND

WHEREAS , the Seller legally and beneficially owns 10,000 ordinary shares, representing twenty (20) percent of the issued and outstanding ordinary shares (the “ Shares ”) of Alliance BMP Limited, a company incorporated in England and Wales with registered number 06056032 having its registered address at 2 The Heights, Brooklands, Weybridge, Surrey, KT13 0NY (the “ Company ”); and

WHEREAS , the Seller desires to sell and the Purchaser desires to buy the Shares for the purchase price and pursuant to the terms and conditions as further set forth below.

WITNESSETH

NOW, THEREFORE , the Parties, intending to be legally bound hereby, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, and in consideration of the mutual covenants contained herein, hereby agree as follows:

For convenience, certain terms used in more than one part of this Agreement are listed in alphabetical order and defined or referred to below (such terms as well as any other terms defined elsewhere in this Agreement shall be equally applicable to both the singular and plural forms of the terms defined).

“ Agreed Form ” shall mean the form of the relevant document in the terms agreed between the Seller and the Purchaser prior to the execution of this Agreement and signed or initialed for identification purposes only by or on behalf of the Seller and the Purchaser (in each case with such amendments as may be agreed or on behalf of the Seller and the Purchaser).

“ Agreed Statement ” shall have the meaning set forth in Section 9.1.

“ Agreement ” shall mean this Share Purchase Agreement.

“ Business Day ” shall mean a day other than a Saturday, Sunday or other day on which commercial banks in Philadelphia, Pennsylvania, New York City, New York, and the United Kingdom are authorized or required by law to be closed.

“ Claim Notice” shall have the meaning set forth in Section 9.3(d).

“ Company ” shall have the meaning set forth in the recitals.

“ Damages ” shall have the meaning set forth in Section 7.2.

“ Escrow Agent ” shall mean Baker & McKenzie LLP of 100 New Bridge Street, London EC4V 6JA.

“ Escrow Documents ” shall mean;

each in respect of the Second Payment Shares.

“ Escrow Instruction Letter ” shall mean the letter agreement of the same date as this Agreement between: (1) the Escrow Agent; (2) the Seller; and (3) the Purchaser, in relation to the Escrow Documents, in the Agreed Form.

“ First Payment ” shall have the meaning set forth in Section 2.2(a).

“ First Payment Date ” shall mean a day falling on or before the day which is 15 Business Days following the Signing Date.

“ Liens ” shall mean, with respect to any Person, any mortgage, lien, pledge, charge, security interest, title retention or other encumbrance, or any interest or title of any third party including vendor, lessor, lender or other secured party to or of such Person under any agreement, arrangement or capital lease, upon or with respect to any property or asset of such Person (including any right to acquire, option, right of first refusal or right of pre-emption) the effect of which is the creation of security, or any other interest equity or other right of any of third party (including, without limitation, in the case of stock, stockholder agreements, voting trust agreements and all similar arrangements) or any agreement or arrangement to create any of the same.

“ Notice ” shall have the meaning set forth in Section 9.3.

“ Parties ” shall have the meaning set forth in the preamble and “ Party ” shall be construed accordingly.

“ Person ” shall mean an individual, partnership, corporation, limited liability company, association, trust, unincorporated organization, or a government or agency or political subdivision thereof.

“ Press Response ” shall mean the questions and answers to be given by the Parties in relation to any press or other third party enquiries in relation to this Agreement or the Transaction, in the Agreed Form.

“ Purchaser ” shall have the meaning set forth in the preamble.

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“ Purchaser Indemnified Parties ” shall have the meaning set forth in Section 7.3.

“ Relevant Date ” shall have the meaning set forth in Section 2.5.

“ Second Payment ” shall have the meaning set forth in Section 2.2(b).

“ Second Payment Date ” shall have the meaning set forth in Section 2.2 (b).

“ Second Payment Shares ” shall mean half of the Shares (being 5,000 ordinary shares in the capital of the Company).

“ Seller ” shall have the meaning set forth in the preamble.

“ Seller’s Group ” shall mean the group of companies comprising the Seller, any holding company from time to time of the Seller and any subsidiary of the Seller or of any such holding company and “member of the Seller’s Group” shall be construed accordingly.

“ Seller Indemnified Parties ” shall have the meaning set forth in Section 7.2.

“ Seller’s Solicitors ” shall mean Morgan Lewis & Bockius of Condor House, 5-10 St Paul’s Churchyard, London EC4M 8AL.

“ Service Agreement ” shall mean the agreement to be entered into on the Signing Date between: (1) the Company; and (2) David Gao, in the Agreed Form.

“ Share Payment ” shall have the meaning set forth in Section 2.2.

“ Shareholders Agreement ” means the Shareholders Agreement entered into by the Parties and the Company on 18 January 2007.

“ Shares ” shall have the meaning set forth in the recitals.

“ Signing ” shall have the meaning set forth in Section 3.1.

“ Signing Date ” shall have the meaning set forth in Section 3.1.

“ Statement ” shall have the meaning set forth in Section 9.1.

“Termination Date ” shall have the meaning set forth in Section 8(c).

“ Transaction ” shall mean the sale of the Shares by the Seller to the Purchaser and the other actions contemplated hereby.

“ USD ” means the lawful currency of the United States as of the date of this Agreement.

“ Warranties ” shall mean the representations and warranties given in Section 5.

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2.1 Purchase and Sale of the Shares . Subject to the terms and conditions of this Agreement, on the Signing Date the Purchaser (relying on the Warranties and other obligations of the Seller) shall buy from the Seller, and the Seller, as legal and beneficial owner, shall sell to the Purchaser, with full title guarantee all rights, title and interest in the Shares, including all rights now or hereafter attaching to them including, without limitation, all rights to any dividend or other distribution declared, made or paid after the Signing Date.

2.2 Purchase Price . The total purchase price for the Shares is an aggregate of USD15.1 million to be paid by the Purchaser to the Seller (the “ Share Payment ”) in two installments as follows:

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2.3 The Shares . Other than the representation and warranties of Seller in Section 5.1 and the undertaking as to full title guarantee in Section 2.1, the Seller makes no representations or warranties regarding the Shares of any kind, expressed or implied, and all such representations and warranties are hereby expressly disclaimed by the Seller.

2.4 Conditions to the Obligations of the Seller at the Signing Date . The obligations of the Seller at the Signing Date are subject to the conditions precedent that:

(a) the representations and warranties of the Purchaser are true and correct in all respects as of the Signing Date; and

(b) the Purchaser has complied in all material respects with all covenants, obligations and agreements to be performed by it on or prior to the Signing Date.

2.5 Conditions to the Obligations of the Purchaser . The obligations of the Purchaser at each of the Signing Date, the First Payment Date and the Second Payment Date (each a “Relevant Date”) are subject to the conditions precedent that:

(a) the representations and warranties of the Seller are true and correct in all respects as at each Relevant Date; and

(b) the Seller has complied in all material respects with all covenants, obligations and agreements to be performed by it (including, for the avoidance of doubt, pursuant to Section 7.3) and the Purchaser has not served a Claim Notice on or prior to each Relevant Date.

3.1 Location, Date . The signing and completion of this Agreement (the “ Signing ”) shall take place on the date hereof, or on such other date and at such time as may be mutually agreed upon by the Parties, at the offices of Morgan, Lewis & Bockius, Condor House, 5-10 St Paul’s Churchyard, London EC4M 8AL, England, unless the Parties agree in writing to another date or place. The date on which the Signing occurs is referred to herein as the “ Signing Date .” The delivery of documents at or prior to the Signing, including this Agreement but not including the certificate(s) representing the Shares, may be made by facsimile transmission or email.

3.2 Sale of All Shares . The Purchaser shall not be obliged to complete the purchase of any of the Shares unless the sale of all of the Shares is completed simultaneously in accordance with this Agreement.

3.3 Passing of Title . For the avoidance of doubt, the Parties agree that:

(a) the legal and beneficial title in all of the Shares shall pass to the Purchaser on the Signing Date (including, for the avoidance of doubt, all voting rights attaching to the Shares); and

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(b) in the event that the Purchaser fails to make or procure the making of the Second Payment on or before the Second Payment Date and, subject to the Seller complying with its obligations pursuant to Section 2.5 to the satisfaction of the Purchaser, the Escrow Documents shall be released to the Seller subject to and in accordance with the terms and conditions of the Escrow Instruction Letter.

3.4 Deliveries . Subject to the terms and conditions contained herein, at the Signing Date:

(a) the Seller shall deliver to the Purchaser:

(i) the duly executed transfer in respect of the Shares into the name of the Purchaser (or its nominee);

(ii) the deed of indemnity for lost share certificates in respect of the Shares;

(iii) letter of resignation, in terms acceptable to the Purchaser, from David Gao as a director of the Company);

(iv) three original copies of the Escrow Instruction Letter duly executed on behalf of the Seller;

(v) a certified copy of the board resolutions of the Seller in the agreed form approving this Transaction and authorizing the signing and performance by the Seller of this Agreement and approving any action or the performance of any other business which may be necessary or desirable to give full and valid effect to the sale and purchase of the Shares or as the Purchaser may reasonably require;

(vi) a duly executed deed of release under seal, in terms acceptable to the Purchaser, releasing the Company from any liability whatsoever (whether actual or contingent) which may be owing to the Seller by the Company;

(vii) all such other documents, including such waivers and consents as the Purchaser may require to enable the Purchaser to be registered as holder of any of the Shares;

(viii) a duly executed irrevocable power of attorney in the agreed form in respect of the Shares enabling the Purchaser (during the period prior to the registration of the transfer of the Shares) to exercise all voting and other rights attaching to the Shares; and

(ix) two original copies of the Service Agreement, duly executed on behalf of each of the Company and David Gao;

(b) the Seller shall cause the directors of the Company to hold a meeting of the board of directors of the Company at which the directors shall consult and pass resolutions in the agreed form to approve the registration of the Purchaser as the legal owner of the Shares subject only to the production of duly stamped and completed transfers in respect of the Shares;

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(c) the Purchaser shall deliver to the Seller three original copies of the Escrow Instruction Letter duly executed on behalf of the Purchaser and the Escrow Agent.

4.1 Authority; Binding Effect . The Purchaser has all requisite corporate power and authority to execute and deliver this Agreement. All necessary action, corporate or otherwise, required to have been taken by or on behalf of the Purchaser under any applicable law, its organizational documents or otherwise to authorize (a) the approval, execution and delivery on its behalf of this Agreement, and (b) its performance of its obligations under this Agreement has been taken. This Agreement constitutes the valid and binding agreement of the Purchaser, enforceable against it in accordance with its terms, except (y) as the same may be limited by applicable bankruptcy, insolvency, moratorium or similar laws of general application relating to or affecting creditors’ rights, including, without limitation, the effect of statutory or other laws regarding fraudulent conveyances and preferential transfers and (z) for the limitations imposed by general principles of equity.

4.2 No Conflict; Approvals . The execution, delivery and performance of this Agreement and the consummation by the Purchaser of the Transaction will not (a) result in a violation of the Purchaser’s organizational and charter documents, (b) conflict with any agreement, indenture or instrument to which the Purchaser is a party or (c) result in a violation of any